Re: [RESOLVED] Re: EPROM baking
It might be a good idea to put color codes like on a resistor on the connector plug. You know, green for 5 gold for + center pin and silver for - center pin. No gold or silver band would be AC. Brown Red Gold would be 12VDC + on center pin. Dwight From: cctalk on behalf of Chuck Guzis via cctalk Sent: Tuesday, February 6, 2018 7:28:38 AM To: Tor Arntsen via cctalk Subject: Re: [RESOLVED] Re: EPROM baking On 02/06/2018 12:05 AM, Tor Arntsen via cctalk wrote: > .. which led me to accidentally power a USB hub with 12V instead of > 5V - the power supplies looked the same, had the same plug, and I > couldn't read the tiny writing on the warts. That blew the nicest > notebook PC I've ever found - I bought it in Japan at a special > price, the normal price is out of my league. I've done worse--used an AC-supply wall wart on a piece of equipment. Poor thing didn't stand a chance. You'd have thought that after all these years, some sort of keying system would have been developed, but I guess not. --Chuck
Re: [RESOLVED] Re: EPROM baking
On Mon, Feb 05, 2018 at 11:06:29AM -0800, Chuck Guzis via cctalk wrote: > On 02/05/2018 10:20 AM, Mark G Thomas via cctalk wrote: > > > 2) Many of the chips were failing to program because my Batronix > >programmer apparently requires more current than my USB port provides. > >This surprised me because I have been programming chips for years > >using this programmer on this computer port successfully, and this > >is the first I have had the problem. Using a Anker powered USB hub solved > >things. My Batronix programmer even arrived with a cheap powered hub > >when I ordered it, but I never used it because it was shipped with an > >incompatible wall wart, but looking at it in the box gave me the idea > >that this might be the issue. > > You should be aware that many "thin" Far East USB cables will not pass > the full USB 1.5A current without substantial voltage drop. I recently Maximum current from a standard USB 2.0 port is 500 mA, USB 3.0 ups that to 900 mA. To really get some power via USB, you have to go all the way to USB C connectors and PD (power delivery), where you easily get 65 W, at the expense of quite bit of complexity on both ends of the cable. Of course there are plenty of USB chargers that are all over the map - and they usually just abuse USB cabling as power wiring, trying to cram 2 A or more down it - which might not work if whoever made the cable "saved" a bit too aggressively on the copper. > ran into this with a new LG portable DVD drive. It refused to operate, > even though I'd just taken it out of the box. I replaced the "thin" > USB cable with several other "thin" ones that I had with the same > result. Finally, in desperation, I located a "thick" USB cable, plugged > the drive in, and discovered that it worked just fine. > > Moral: There's a lot of garbage out there. Is there ever, sadly. Including dangerous garbage - with the power levels of USB C and PD, bad cables (and chargers) can actually by a serious fire risk. Fortunately, Benson Leung is on a crusade against this: https://thenextweb.com/insider/2015/11/05/a-google-engineer-is-reviewing-usb-c-cables-on-amazon-and-its-awesome/ Kind regards, Alex. -- "Opportunity is missed by most people because it is dressed in overalls and looks like work." -- Thomas A. Edison
Re: [RESOLVED] Re: EPROM baking
On 02/06/2018 12:05 AM, Tor Arntsen via cctalk wrote: > .. which led me to accidentally power a USB hub with 12V instead of > 5V - the power supplies looked the same, had the same plug, and I > couldn't read the tiny writing on the warts. That blew the nicest > notebook PC I've ever found - I bought it in Japan at a special > price, the normal price is out of my league. I've done worse--used an AC-supply wall wart on a piece of equipment. Poor thing didn't stand a chance. You'd have thought that after all these years, some sort of keying system would have been developed, but I guess not. --Chuck
Re: [RESOLVED] Re: EPROM baking
On 5 February 2018 at 20:06, Chuck Guzis via cctalk wrote: > I have a similar gripe with barrel connectors, > which don't seem to enforce any standard at all regarding polarity or AC > vs. DC. .. which led me to accidentally power a USB hub with 12V instead of 5V - the power supplies looked the same, had the same plug, and I couldn't read the tiny writing on the warts. That blew the nicest notebook PC I've ever found - I bought it in Japan at a special price, the normal price is out of my league. Since then I have bought a Dymo and, armed with a magnifying glass, went through all the chargers and warts I own and labelled them. Which I should have done *before* the accident of course. But what if there was some kind of standard for barrel connectors instead.. sigh.
Re: [RESOLVED] Re: EPROM baking
On Mon, Feb 5, 2018 at 12:06 PM, Chuck Guzis via cctalk < cctalk@classiccmp.org> wrote: > You should be aware that many "thin" Far East USB cables will not pass > the full USB 1.5A current without substantial voltage drop. > "Full USB current" is only 0.5A for USB 2, and 0.9A for USB 3. Any USB device that needs more current than that should be using the Battery Charging, Power Delivery, or Type C options, or some combination thereof, and suitable cabling. However, I don't disagree with your assertion that there are a lot of really crappy USB cables out there.
Re: [RESOLVED] Re: EPROM baking
On 02/05/2018 01:02 PM, Bill Degnan via cctalk wrote: > I was going to say...I would not have thought any USB-powered prom > programmer to be the best solution. I have two programmers both have their > own wall power connectors and they're reliable. I am not saying that it > would not be possible that an USB-powered prom programmer would work, but > I'd personally want to stick with something with some legroom. I always > measure my USB supplies and cables' output to separate out the ones that > don't provide enough umph from those that do. > Happy computing I don't use one now, but I used to have a USB-powered programmer and it worked okay for GALs and 27C UV EPROMs as well as EEPROMs. However, if I were using older parts, I'm not so sure. The interesting thing is that upon opening the thing up, you could see pads for a wall-wart barrel jack (unpopulated). So who knows, perhaps Bill's USB programmer is similarly equipped. I still use an older Xeltek Superpro for most things. It does the job. --Chuck
Re: [RESOLVED] Re: EPROM baking
On 2018-02-05 8:00 PM, Chuck Guzis via cctalk wrote: On 02/05/2018 01:02 PM, Bill Degnan via cctalk wrote: I was going to say...I would not have thought any USB-powered prom programmer to be the best solution. I have two programmers both have their own wall power connectors and they're reliable. I am not saying that it would not be possible that an USB-powered prom programmer would work, but I'd personally want to stick with something with some legroom. I always measure my USB supplies and cables' output to separate out the ones that don't provide enough umph from those that do. Happy computing I don't use one now, but I used to have a USB-powered programmer and it worked okay for GALs and 27C UV EPROMs as well as EEPROMs. However, if I were using older parts, I'm not so sure. The interesting thing is that upon opening the thing up, you could see pads for a wall-wart barrel jack (unpopulated). So who knows, perhaps Bill's USB programmer is similarly equipped. I still use an older Xeltek Superpro for most things. It does the job. --Chuck I have a USB programmer I never use, the electronics in it where too weak to drive NMOS EPROMs even with external power but was ok with CMOS parts. I have an old Xeltex Unipro and a Superpro as well as a more mdern parallel port Xeltex superpro/280 and a Advin badged USB Xeltex that uses external power they are all much more reliable but I have found a couple programming algorithms for small AMD PLDs that are broken. The old Unipro came in handy when I needed to program some bipolar PROMs. Paul.
Re: [RESOLVED] Re: EPROM baking
> > > > On 02/05/2018 02:06 PM, Chuck Guzis via cctalk wrote: > > On 02/05/2018 10:20 AM, Mark G Thomas via cctalk wrote: > > > >> 2) Many of the chips were failing to program because my Batronix > >> programmer apparently requires more current than my USB port > provides. > >> This surprised me because I have been programming chips for years > >> using this programmer on this computer port successfully, and this > >> is the first I have had the problem. Using a Anker powered USB hub > solved > >> things. My Batronix programmer even arrived with a cheap powered hub > >> when I ordered it, but I never used it because it was shipped with > an > >> incompatible wall wart, but looking at it in the box gave me the > idea > >> that this might be the issue. > > You should be aware that many "thin" Far East USB cables will not pass > > the full USB 1.5A current without substantial voltage drop. I recently > > ran into this with a new LG portable DVD drive. It refused to operate, > > even though I'd just taken it out of the box. I replaced the "thin" > > USB cable with several other "thin" ones that I had with the same > > result. Finally, in desperation, I located a "thick" USB cable, plugged > > the drive in, and discovered that it worked just fine. > > > > Moral: There's a lot of garbage out there. > > > > Rant: The whole scheme of supplying anything but low-current using USB > > is a terrible idea. I have a similar gripe with barrel connectors, > > which don't seem to enforce any standard at all regarding polarity or AC > > vs. DC. > > > > For my own projects I've taken to using mini XLR connectors. Perhaps not > > optimal, but they're rugged enough. > > > > --Chuck > > > My EPROM Programmers all have a connection foir external power > > specifically because sometimes USB can't provide the needed current. > > > bill I was going to say...I would not have thought any USB-powered prom programmer to be the best solution. I have two programmers both have their own wall power connectors and they're reliable. I am not saying that it would not be possible that an USB-powered prom programmer would work, but I'd personally want to stick with something with some legroom. I always measure my USB supplies and cables' output to separate out the ones that don't provide enough umph from those that do. Happy computing Bill
Re: [RESOLVED] Re: EPROM baking
My EPROM Programmers all have a connection foir external power specifically because sometimes USB can't provide the needed current. bill On 02/05/2018 02:06 PM, Chuck Guzis via cctalk wrote: > On 02/05/2018 10:20 AM, Mark G Thomas via cctalk wrote: > >> 2) Many of the chips were failing to program because my Batronix >> programmer apparently requires more current than my USB port provides. >> This surprised me because I have been programming chips for years >> using this programmer on this computer port successfully, and this >> is the first I have had the problem. Using a Anker powered USB hub solved >> things. My Batronix programmer even arrived with a cheap powered hub >> when I ordered it, but I never used it because it was shipped with an >> incompatible wall wart, but looking at it in the box gave me the idea >> that this might be the issue. > You should be aware that many "thin" Far East USB cables will not pass > the full USB 1.5A current without substantial voltage drop. I recently > ran into this with a new LG portable DVD drive. It refused to operate, > even though I'd just taken it out of the box. I replaced the "thin" > USB cable with several other "thin" ones that I had with the same > result. Finally, in desperation, I located a "thick" USB cable, plugged > the drive in, and discovered that it worked just fine. > > Moral: There's a lot of garbage out there. > > Rant: The whole scheme of supplying anything but low-current using USB > is a terrible idea. I have a similar gripe with barrel connectors, > which don't seem to enforce any standard at all regarding polarity or AC > vs. DC. > > For my own projects I've taken to using mini XLR connectors. Perhaps not > optimal, but they're rugged enough. > > --Chuck > >
Re: [RESOLVED] Re: EPROM baking
On 02/05/2018 10:20 AM, Mark G Thomas via cctalk wrote: > 2) Many of the chips were failing to program because my Batronix >programmer apparently requires more current than my USB port provides. >This surprised me because I have been programming chips for years >using this programmer on this computer port successfully, and this >is the first I have had the problem. Using a Anker powered USB hub solved >things. My Batronix programmer even arrived with a cheap powered hub >when I ordered it, but I never used it because it was shipped with an >incompatible wall wart, but looking at it in the box gave me the idea >that this might be the issue. You should be aware that many "thin" Far East USB cables will not pass the full USB 1.5A current without substantial voltage drop. I recently ran into this with a new LG portable DVD drive. It refused to operate, even though I'd just taken it out of the box. I replaced the "thin" USB cable with several other "thin" ones that I had with the same result. Finally, in desperation, I located a "thick" USB cable, plugged the drive in, and discovered that it worked just fine. Moral: There's a lot of garbage out there. Rant: The whole scheme of supplying anything but low-current using USB is a terrible idea. I have a similar gripe with barrel connectors, which don't seem to enforce any standard at all regarding polarity or AC vs. DC. For my own projects I've taken to using mini XLR connectors. Perhaps not optimal, but they're rugged enough. --Chuck
[RESOLVED] Re: EPROM baking
Hi, Please see resolution below, if you are curious about how this turned out. On Wed, Dec 20, 2017 at 09:18:50PM -0500, Mark G Thomas via cctalk wrote: > Hi, > > > On Wed, Dec 13, 2017 at 9:08 AM, Mark G Thomas via cctalk < > > cctalk@classiccmp.org> wrote: > > > > > Hi, > > > > > > I am working on several projects requiring 2708 and 2716 EPROMs, and > > > am finding some of my chips will not erase, and some will not take > > > a program. I've also learned more in the past week than I wanted > > > to know about repairing Data-I/O 29a/b programmers. > > > > > > I vaguely remember in the 1990s baking such EPROMs in the oven, but > > > I do not remember temperature or time. I was surprised that Google > > > didn't turn up anything useful with this info. > > > > > > I'm sure someone here will have some notes on EPROM baking. > > > > > > Mark > > > > Mark, > > > > If this is an issue about reviving bad eproms? I assume you have tried the > > regular stuff. > > > > What process are you using now to erase 2708/16's? I have a simple eraser > > unit and it seems to always work. Some eproms go bad but I never have > > issues with erasing them. My point is that maybe you need a better prom > > eraser unit. > > They seem to erase fine, using a PRO-LOG 9103 eraser (box, timer, tube...) > > > I would avoid baking them until you have exhausted other > > options. Not sure what others think. This topic has come up before here, > > about putting them outside and all that. The erasers are all over ebay, > > and the hardware store is full of the correct types of lighting, why not > > make a box that will do the job?I assume there is more to it that > > simply erasing them. > > > > > > Bill After more experimentation I came to the following conclusions. 1) Some of my chips are legitimately bad, erasing fine but won't take a program. 2) Many of the chips were failing to program because my Batronix programmer apparently requires more current than my USB port provides. This surprised me because I have been programming chips for years using this programmer on this computer port successfully, and this is the first I have had the problem. Using a Anker powered USB hub solved things. My Batronix programmer even arrived with a cheap powered hub when I ordered it, but I never used it because it was shipped with an incompatible wall wart, but looking at it in the box gave me the idea that this might be the issue. 3) I thought I had ruled out the programmer (#2) because of troubles programming those same chips using another programmer, but I probably had the wrong chip type selected, or simply failed on some of the #1 chips so assumed that was my only problem. Mark -- Mark G. Thomas (m...@misty.com), KC3DRE
Re: EPROM baking
All chips should have windows. On Sat, Dec 23, 2017 at 11:04 PM, Chuck Guzis via cctalk < cctalk@classiccmp.org> wrote: > On 12/23/2017 08:47 PM, Ethan Dicks via cctalk wrote: > > > I did that once and had the same experience - a glow from under the > > lid, but no smoke... and put right-way-round, was still programmable > > and verifiable. > > Well, that's one way to "bake" an EPROM! > > --Chuck > > >
Re: EPROM baking
On 12/23/2017 08:47 PM, Ethan Dicks via cctalk wrote: > I did that once and had the same experience - a glow from under the > lid, but no smoke... and put right-way-round, was still programmable > and verifiable. Well, that's one way to "bake" an EPROM! --Chuck
Re: EPROM baking
On Sat, Dec 23, 2017 at 12:04 PM, Jon Elson via cctalk wrote: > I made my own 2716-2764 programmer MANY years ago. On a few occasions I put > an EPROM in wrong and saw the bonding wires light up! I killed power and > corrected the mistake, and the EPROM worked fine. I did that once and had the same experience - a glow from under the lid, but no smoke... and put right-way-round, was still programmable and verifiable. -ethan
Re: EPROM baking
On 12/23/2017 10:00 AM, dwight via cctalk wrote: When I had access to a wire bonder, we took EPROMs that had been plugged in upside down and removed the lids. We'd see a blown wire and replace it. On several of these parts we found that 100% worked. So it would seem that no silicon damage was done, just the bonding wire was blown like a fuse. I made my own 2716-2764 programmer MANY years ago. On a few occasions I put an EPROM in wrong and saw the bonding wires light up! I killed power and corrected the mistake, and the EPROM worked fine. Jon
Re: EPROM baking
When I had access to a wire bonder, we took EPROMs that had been plugged in upside down and removed the lids. We'd see a blown wire and replace it. On several of these parts we found that 100% worked. So it would seem that no silicon damage was done, just the bonding wire was blown like a fuse. I doubt this method would repair those blown from excess programming voltage. Dwight From: cctalk on behalf of Curious Marc via cctalk Sent: Friday, December 22, 2017 9:04:07 PM To: Mark G Thomas; General Discussion: On-Topic and Off-Topic Posts Subject: Re: EPROM baking I see the same things. Some chips just won't reprogram. Symptoms include failure to program just like you, but also "chip backwards" errors. Can't remember the chip brands, I just toss them out when that happens. I have not found any way to resuscitate them. Maybe ~10% of the chips I tried had this, so rather frequent, but never any from new old stock. The failed ones were all previously programmed chips, just erased. Marc On Dec 20, 2017, at 6:18 PM, Mark G Thomas via cctalk wrote: My stash of TI and NEC 2732s seem to have the disease, but my ST, Mitsubishi, and several others program fine. In the case of a bunch of 2732s, I have tried both a vintage DataI/O 29A programmer and a modern Batronix programmer, with the same results. I don't think I have a programmer problem. I still swear someone in the late 80's had me baking EPROMs in an oven to restore their programability, but I don't remember the specifics. I tried a few at 450F for 15 minutes, but they still won't program. Mark -- Mark G. Thomas (m...@misty.com), KC3DRE
Re: EPROM baking
I see the same things. Some chips just won't reprogram. Symptoms include failure to program just like you, but also "chip backwards" errors. Can't remember the chip brands, I just toss them out when that happens. I have not found any way to resuscitate them. Maybe ~10% of the chips I tried had this, so rather frequent, but never any from new old stock. The failed ones were all previously programmed chips, just erased. Marc On Dec 20, 2017, at 6:18 PM, Mark G Thomas via cctalk wrote: My stash of TI and NEC 2732s seem to have the disease, but my ST, Mitsubishi, and several others program fine. In the case of a bunch of 2732s, I have tried both a vintage DataI/O 29A programmer and a modern Batronix programmer, with the same results. I don't think I have a programmer problem. I still swear someone in the late 80's had me baking EPROMs in an oven to restore their programability, but I don't remember the specifics. I tried a few at 450F for 15 minutes, but they still won't program. Mark -- Mark G. Thomas (m...@misty.com), KC3DRE
Re: EPROM baking
If you've over voltages them, they are history. If the ground pin is not making good contact and you try to program them, they will also be history. Dwight From: cctalk on behalf of Pete Rittwage via cctalk Sent: Thursday, December 21, 2017 7:05:06 AM To: Mark G Thomas; General Discussion: On-Topic Posts Cc: cctalk@classiccmp.org Subject: Re: EPROM baking > Hi, > >> On Wed, Dec 13, 2017 at 9:08 AM, Mark G Thomas via cctalk < >> cctalk@classiccmp.org> wrote: >> >> > Hi, >> > >> > I am working on several projects requiring 2708 and 2716 EPROMs, and >> > am finding some of my chips will not erase, and some will not take >> > a program. I've also learned more in the past week than I wanted >> > to know about repairing Data-I/O 29a/b programmers. >> > >> > I vaguely remember in the 1990s baking such EPROMs in the oven, but >> > I do not remember temperature or time. I was surprised that Google >> > didn't turn up anything useful with this info. >> > >> > I'm sure someone here will have some notes on EPROM baking. >> > >> > Mark >> >> Mark, >> >> If this is an issue about reviving bad eproms? I assume you have tried >> the >> regular stuff. >> >> What process are you using now to erase 2708/16's? I have a simple >> eraser >> unit and it seems to always work. Some eproms go bad but I never have >> issues with erasing them. My point is that maybe you need a better prom >> eraser unit. > > They seem to erase fine, using a PRO-LOG 9103 eraser (box, timer, tube...) > >> I would avoid baking them until you have exhausted other >> options. Not sure what others think. This topic has come up before >> here, >> about putting them outside and all that. The erasers are all over ebay, >> and the hardware store is full of the correct types of lighting, why not >> make a box that will do the job?I assume there is more to it that >> simply erasing them. >> >> >> Bill > > Erasing seems to work fine. It's the re-programming them that is the > problem. > > On Wed, Dec 13, 2017 at 02:49:39PM +, dwight via cctalk wrote: >> When I was at Intel, years ago, I recall the baking was only to repair >> the retention of the EPROMs. It was not to fix random failures. >> >> It sounds like your EPROMs have various failures that wouldn't be helped >> by baking. >> >> Each time the EPROM is programmed, there is a slight increase in the >> leakage of the floating gate. This was typical after thousands of >> program/erase cycles. Baking them repaired the damage to the insulating >> layer that was damaged. >> >> Dwight > > I don't think these chips have been reprogrammed many times. It seems more > age related, affecting some brands/models in my spares but not others. > > The failure mode is the chips erase successfully, but any attempt to > program them fails, and they still test blank and read back "...". > Some of these were chips I erased years ago before putting in my spares > drawer, and some had fine working code on them, but I erased them to > re-program with a newer version of software on them, to discover I could > not. > > My stash of TI and NEC 2732s seem to have the disease, but my ST, > Mitsubishi, and several others program fine. > > In the case of a bunch of 2732s, I have tried both a vintage DataI/O 29A > programmer and a modern Batronix programmer, with the same results. > I don't think I have a programmer problem. > > I still swear someone in the late 80's had me baking EPROMs in an oven > to restore their programability, but I don't remember the specifics. I > tried a few at 450F for 15 minutes, but they still won't program. > Are you positive you have the programming voltage right? I have a box of really old ones and every time I have to research a little to find the right voltage for different brands. All 27128's are not the same, for example. Some are 12V, some may be 25V (for example). My programmer only has one setting in the software, and I have to change jumpers to modify programming voltage. My USB programmer won't touch any of the old ones because I assume it can't provide enough voltage/current for them. -Pete Rittwage
Re: EPROM baking
> Hi, > >> On Wed, Dec 13, 2017 at 9:08 AM, Mark G Thomas via cctalk < >> cctalk@classiccmp.org> wrote: >> >> > Hi, >> > >> > I am working on several projects requiring 2708 and 2716 EPROMs, and >> > am finding some of my chips will not erase, and some will not take >> > a program. I've also learned more in the past week than I wanted >> > to know about repairing Data-I/O 29a/b programmers. >> > >> > I vaguely remember in the 1990s baking such EPROMs in the oven, but >> > I do not remember temperature or time. I was surprised that Google >> > didn't turn up anything useful with this info. >> > >> > I'm sure someone here will have some notes on EPROM baking. >> > >> > Mark >> >> Mark, >> >> If this is an issue about reviving bad eproms? I assume you have tried >> the >> regular stuff. >> >> What process are you using now to erase 2708/16's? I have a simple >> eraser >> unit and it seems to always work. Some eproms go bad but I never have >> issues with erasing them. My point is that maybe you need a better prom >> eraser unit. > > They seem to erase fine, using a PRO-LOG 9103 eraser (box, timer, tube...) > >> I would avoid baking them until you have exhausted other >> options. Not sure what others think. This topic has come up before >> here, >> about putting them outside and all that. The erasers are all over ebay, >> and the hardware store is full of the correct types of lighting, why not >> make a box that will do the job?I assume there is more to it that >> simply erasing them. >> >> >> Bill > > Erasing seems to work fine. It's the re-programming them that is the > problem. > > On Wed, Dec 13, 2017 at 02:49:39PM +, dwight via cctalk wrote: >> When I was at Intel, years ago, I recall the baking was only to repair >> the retention of the EPROMs. It was not to fix random failures. >> >> It sounds like your EPROMs have various failures that wouldn't be helped >> by baking. >> >> Each time the EPROM is programmed, there is a slight increase in the >> leakage of the floating gate. This was typical after thousands of >> program/erase cycles. Baking them repaired the damage to the insulating >> layer that was damaged. >> >> Dwight > > I don't think these chips have been reprogrammed many times. It seems more > age related, affecting some brands/models in my spares but not others. > > The failure mode is the chips erase successfully, but any attempt to > program them fails, and they still test blank and read back "...". > Some of these were chips I erased years ago before putting in my spares > drawer, and some had fine working code on them, but I erased them to > re-program with a newer version of software on them, to discover I could > not. > > My stash of TI and NEC 2732s seem to have the disease, but my ST, > Mitsubishi, and several others program fine. > > In the case of a bunch of 2732s, I have tried both a vintage DataI/O 29A > programmer and a modern Batronix programmer, with the same results. > I don't think I have a programmer problem. > > I still swear someone in the late 80's had me baking EPROMs in an oven > to restore their programability, but I don't remember the specifics. I > tried a few at 450F for 15 minutes, but they still won't program. > Are you positive you have the programming voltage right? I have a box of really old ones and every time I have to research a little to find the right voltage for different brands. All 27128's are not the same, for example. Some are 12V, some may be 25V (for example). My programmer only has one setting in the software, and I have to change jumpers to modify programming voltage. My USB programmer won't touch any of the old ones because I assume it can't provide enough voltage/current for them. -Pete Rittwage
Re: EPROM baking
Hi, > On Wed, Dec 13, 2017 at 9:08 AM, Mark G Thomas via cctalk < > cctalk@classiccmp.org> wrote: > > > Hi, > > > > I am working on several projects requiring 2708 and 2716 EPROMs, and > > am finding some of my chips will not erase, and some will not take > > a program. I've also learned more in the past week than I wanted > > to know about repairing Data-I/O 29a/b programmers. > > > > I vaguely remember in the 1990s baking such EPROMs in the oven, but > > I do not remember temperature or time. I was surprised that Google > > didn't turn up anything useful with this info. > > > > I'm sure someone here will have some notes on EPROM baking. > > > > Mark > > Mark, > > If this is an issue about reviving bad eproms? I assume you have tried the > regular stuff. > > What process are you using now to erase 2708/16's? I have a simple eraser > unit and it seems to always work. Some eproms go bad but I never have > issues with erasing them. My point is that maybe you need a better prom > eraser unit. They seem to erase fine, using a PRO-LOG 9103 eraser (box, timer, tube...) > I would avoid baking them until you have exhausted other > options. Not sure what others think. This topic has come up before here, > about putting them outside and all that. The erasers are all over ebay, > and the hardware store is full of the correct types of lighting, why not > make a box that will do the job?I assume there is more to it that > simply erasing them. > > > Bill Erasing seems to work fine. It's the re-programming them that is the problem. On Wed, Dec 13, 2017 at 02:49:39PM +, dwight via cctalk wrote: > When I was at Intel, years ago, I recall the baking was only to repair > the retention of the EPROMs. It was not to fix random failures. > > It sounds like your EPROMs have various failures that wouldn't be helped by > baking. > > Each time the EPROM is programmed, there is a slight increase in the leakage > of the floating gate. This was typical after thousands of program/erase > cycles. Baking them repaired the damage to the insulating layer that was > damaged. > > Dwight I don't think these chips have been reprogrammed many times. It seems more age related, affecting some brands/models in my spares but not others. The failure mode is the chips erase successfully, but any attempt to program them fails, and they still test blank and read back "...". Some of these were chips I erased years ago before putting in my spares drawer, and some had fine working code on them, but I erased them to re-program with a newer version of software on them, to discover I could not. My stash of TI and NEC 2732s seem to have the disease, but my ST, Mitsubishi, and several others program fine. In the case of a bunch of 2732s, I have tried both a vintage DataI/O 29A programmer and a modern Batronix programmer, with the same results. I don't think I have a programmer problem. I still swear someone in the late 80's had me baking EPROMs in an oven to restore their programability, but I don't remember the specifics. I tried a few at 450F for 15 minutes, but they still won't program. Mark -- Mark G. Thomas (m...@misty.com), KC3DRE
Re: EPROM baking
Oh, and make sure the quartz window is clean :) I've had sticker residue result in some bits not erasing. Thanks, Jonathan On Wed, Dec 13, 2017 at 12:18 PM, systems_glitch wrote: > The only "baking" I've heard about with EPROMs was *annealing* on the > original prototypes from Intel. I want to say that was before they figured > out UV erasure and were zapping the things with X-rays for erasure. You > won't be doing any EPROM annealing in a home oven :) > > It's been my experience that usually defective 2708s or 2716s will fail to > program, rather than fail to erase. Be aware that some of these old EPROMs > take quite a while to erase. Newer stuff like 2764s are usually done in > around 15 minutes with my old UV eraser, but I've had to run old 2708s and > 1702s for much longer, 30+ minutes usually. I think my eraser uses a 15W > lamp, for reference. > > Try programming all zeros and see if it'll take. If it does, try and erase > them. If you start seeing some bits flip to one but not all of them, > increase exposure time. If you get up around an hour and you still have > zeros in some positions, the EPROM is likely bad. If you're debugging or > developing on something, I wouldn't bother messing around with potentially > bad EPROMs, especially 2716s since those are still pretty available. You > can also drop a 2816 EEPROM in there (there are other pin-compatible > EEPROMs, SEEQ had one, there may be others). > > And, of course, be aware that Texas Instruments' 2716 is its own thing and > not compatible with the common 5V-only 2716s. They called their Intel 2716 > compatible a 2516. > > Thanks, > Jonathan > > On Wed, Dec 13, 2017 at 10:33 AM, Michael Zahorik via cctalk < > cctalk@classiccmp.org> wrote: > >> My homemade 8080 CPM machine used a number of 2708 and 2716 EPROMs. that >> was 40 years ago. This machine is still running and I use it, but since I >> had trouble with the EPROMs, I switched to EEPROMs. I would also be >> interested in hearing about whether or not baking would work and how to do >> the baking, exactly. I have a bunch of old EPROMs, that I figured were >> dead, but maybe not? Mike Zahorik >> >> >> From: Holm Tiffe via cctalk >> To: dwight via cctalk >> Sent: Wednesday, December 13, 2017 9:17 AM >> Subject: Re: EPROM baking >> >> >> Hmm..I've read about that baking in conjunction with 1702A too..but >> don't remember the source of that discussion. I know that ppl suggested >> it for proms that would'nt program correctly... >> >> Regards, >> Holm >> >> dwight via cctalk wrote: >> >> > When I was at Intel, years ago, I recall the baking was only to repair >> the retention of the EPROMs. It was not to fix random failures. >> > >> > It sounds like your EPROMs have various failures that wouldn't be >> helped by baking. >> > >> > Each time the EPROM is programmed, there is a slight increase in the >> leakage of the floating gate. This was typical after thousands of >> program/erase cycles. Baking them repaired the damage to the insulating >> layer that was damaged. >> > >> > Dwight >> > >> > >> > >> > From: cctalk on behalf of william >> degnan via cctalk >> > Sent: Wednesday, December 13, 2017 6:18:16 AM >> > To: Mark G Thomas; General Discussion: On-Topic and Off-Topic Posts >> > Subject: Re: EPROM baking >> > >> > On Wed, Dec 13, 2017 at 9:08 AM, Mark G Thomas via cctalk < >> > cctalk@classiccmp.org> wrote: >> > >> > > Hi, >> > > >> > > I am working on several projects requiring 2708 and 2716 EPROMs, and >> > > am finding some of my chips will not erase, and some will not take >> > > a program. I've also learned more in the past week than I wanted >> > > to know about repairing Data-I/O 29a/b programmers. >> > > >> > > I vaguely remember in the 1990s baking such EPROMs in the oven, but >> > > I do not remember temperature or time. I was surprised that Google >> > > didn't turn up anything useful with this info. >> > > >> > > I'm sure someone here will have some notes on EPROM baking. >> > > >> > > Mark >> > > >> > > >> > > >> > >> > Mark, >> > >> > If this is an issue about reviving bad eproms? I assume you have tried >> the >> > regular stuff. >> > >>
Re: EPROM baking
The only "baking" I've heard about with EPROMs was *annealing* on the original prototypes from Intel. I want to say that was before they figured out UV erasure and were zapping the things with X-rays for erasure. You won't be doing any EPROM annealing in a home oven :) It's been my experience that usually defective 2708s or 2716s will fail to program, rather than fail to erase. Be aware that some of these old EPROMs take quite a while to erase. Newer stuff like 2764s are usually done in around 15 minutes with my old UV eraser, but I've had to run old 2708s and 1702s for much longer, 30+ minutes usually. I think my eraser uses a 15W lamp, for reference. Try programming all zeros and see if it'll take. If it does, try and erase them. If you start seeing some bits flip to one but not all of them, increase exposure time. If you get up around an hour and you still have zeros in some positions, the EPROM is likely bad. If you're debugging or developing on something, I wouldn't bother messing around with potentially bad EPROMs, especially 2716s since those are still pretty available. You can also drop a 2816 EEPROM in there (there are other pin-compatible EEPROMs, SEEQ had one, there may be others). And, of course, be aware that Texas Instruments' 2716 is its own thing and not compatible with the common 5V-only 2716s. They called their Intel 2716 compatible a 2516. Thanks, Jonathan On Wed, Dec 13, 2017 at 10:33 AM, Michael Zahorik via cctalk < cctalk@classiccmp.org> wrote: > My homemade 8080 CPM machine used a number of 2708 and 2716 EPROMs. that > was 40 years ago. This machine is still running and I use it, but since I > had trouble with the EPROMs, I switched to EEPROMs. I would also be > interested in hearing about whether or not baking would work and how to do > the baking, exactly. I have a bunch of old EPROMs, that I figured were > dead, but maybe not? Mike Zahorik > > > From: Holm Tiffe via cctalk > To: dwight via cctalk > Sent: Wednesday, December 13, 2017 9:17 AM > Subject: Re: EPROM baking > > > Hmm..I've read about that baking in conjunction with 1702A too..but > don't remember the source of that discussion. I know that ppl suggested > it for proms that would'nt program correctly... > > Regards, > Holm > > dwight via cctalk wrote: > > > When I was at Intel, years ago, I recall the baking was only to repair > the retention of the EPROMs. It was not to fix random failures. > > > > It sounds like your EPROMs have various failures that wouldn't be helped > by baking. > > > > Each time the EPROM is programmed, there is a slight increase in the > leakage of the floating gate. This was typical after thousands of > program/erase cycles. Baking them repaired the damage to the insulating > layer that was damaged. > > > > Dwight > > > > > > ____ > > From: cctalk on behalf of william > degnan via cctalk > > Sent: Wednesday, December 13, 2017 6:18:16 AM > > To: Mark G Thomas; General Discussion: On-Topic and Off-Topic Posts > > Subject: Re: EPROM baking > > > > On Wed, Dec 13, 2017 at 9:08 AM, Mark G Thomas via cctalk < > > cctalk@classiccmp.org> wrote: > > > > > Hi, > > > > > > I am working on several projects requiring 2708 and 2716 EPROMs, and > > > am finding some of my chips will not erase, and some will not take > > > a program. I've also learned more in the past week than I wanted > > > to know about repairing Data-I/O 29a/b programmers. > > > > > > I vaguely remember in the 1990s baking such EPROMs in the oven, but > > > I do not remember temperature or time. I was surprised that Google > > > didn't turn up anything useful with this info. > > > > > > I'm sure someone here will have some notes on EPROM baking. > > > > > > Mark > > > > > > > > > > > > > Mark, > > > > If this is an issue about reviving bad eproms? I assume you have tried > the > > regular stuff. > > > > What process are you using now to erase 2708/16's? I have a simple > eraser > > unit and it seems to always work. Some eproms go bad but I never have > > issues with erasing them. My point is that maybe you need a better prom > > eraser unit. I would avoid baking them until you have exhausted other > > options. Not sure what others think. This topic has come up before > here, > > about putting them outside and all that. The erasers are all over ebay, > > and the hardware store is full of the correct types of lighting, why not > > make a box that will do the job?I assume there is more to it that > > simply erasing them. > > > > > > Bill > > -- > Technik Service u. Handel Tiffe, www.tsht.de, Holm Tiffe, > Freiberger Straße 42, 09600 Oberschöna, USt-Id: DE253710583 > i...@tsht.de Fax +49 3731 74200 Tel +49 3731 74222 Mobil: 0172 8790 741 > > > > >
Re: EPROM baking
My homemade 8080 CPM machine used a number of 2708 and 2716 EPROMs. that was 40 years ago. This machine is still running and I use it, but since I had trouble with the EPROMs, I switched to EEPROMs. I would also be interested in hearing about whether or not baking would work and how to do the baking, exactly. I have a bunch of old EPROMs, that I figured were dead, but maybe not? Mike Zahorik From: Holm Tiffe via cctalk To: dwight via cctalk Sent: Wednesday, December 13, 2017 9:17 AM Subject: Re: EPROM baking Hmm..I've read about that baking in conjunction with 1702A too..but don't remember the source of that discussion. I know that ppl suggested it for proms that would'nt program correctly... Regards, Holm dwight via cctalk wrote: > When I was at Intel, years ago, I recall the baking was only to repair the > retention of the EPROMs. It was not to fix random failures. > > It sounds like your EPROMs have various failures that wouldn't be helped by > baking. > > Each time the EPROM is programmed, there is a slight increase in the leakage > of the floating gate. This was typical after thousands of program/erase > cycles. Baking them repaired the damage to the insulating layer that was > damaged. > > Dwight > > > > From: cctalk on behalf of william degnan via > cctalk > Sent: Wednesday, December 13, 2017 6:18:16 AM > To: Mark G Thomas; General Discussion: On-Topic and Off-Topic Posts > Subject: Re: EPROM baking > > On Wed, Dec 13, 2017 at 9:08 AM, Mark G Thomas via cctalk < > cctalk@classiccmp.org> wrote: > > > Hi, > > > > I am working on several projects requiring 2708 and 2716 EPROMs, and > > am finding some of my chips will not erase, and some will not take > > a program. I've also learned more in the past week than I wanted > > to know about repairing Data-I/O 29a/b programmers. > > > > I vaguely remember in the 1990s baking such EPROMs in the oven, but > > I do not remember temperature or time. I was surprised that Google > > didn't turn up anything useful with this info. > > > > I'm sure someone here will have some notes on EPROM baking. > > > > Mark > > > > > > > > Mark, > > If this is an issue about reviving bad eproms? I assume you have tried the > regular stuff. > > What process are you using now to erase 2708/16's? I have a simple eraser > unit and it seems to always work. Some eproms go bad but I never have > issues with erasing them. My point is that maybe you need a better prom > eraser unit. I would avoid baking them until you have exhausted other > options. Not sure what others think. This topic has come up before here, > about putting them outside and all that. The erasers are all over ebay, > and the hardware store is full of the correct types of lighting, why not > make a box that will do the job? I assume there is more to it that > simply erasing them. > > > Bill -- Technik Service u. Handel Tiffe, www.tsht.de, Holm Tiffe, Freiberger Straße 42, 09600 Oberschöna, USt-Id: DE253710583 i...@tsht.de Fax +49 3731 74200 Tel +49 3731 74222 Mobil: 0172 8790 741
RE: EPROM baking
-Original Message- > From: cctalk [mailto:cctalk-boun...@classiccmp.org] On Behalf Of Mark G > Thomas via cctalk > Sent: 13 December 2017 14:09 > To: CCtalk > Subject: EPROM baking > > Hi, > > I am working on several projects requiring 2708 and 2716 EPROMs, and am > finding some of my chips will not erase, and some will not take a program. > I've also learned more in the past week than I wanted to know about > repairing Data-I/O 29a/b programmers. > Any clues on resources for this. Mine seems to read but gives over current warnings when I ask it to program ROMS.. > I vaguely remember in the 1990s baking such EPROMs in the oven, but I do > not remember temperature or time. I was surprised that Google didn't turn > up anything useful with this info. > > I'm sure someone here will have some notes on EPROM baking. > > Mark > > -- > Mark G. Thomas (m...@misty.com), KC3DRE Dave Wade G4UGM & EA7KAE
Re: EPROM baking
Hmm..I've read about that baking in conjunction with 1702A too..but don't remember the source of that discussion. I know that ppl suggested it for proms that would'nt program correctly... Regards, Holm dwight via cctalk wrote: > When I was at Intel, years ago, I recall the baking was only to repair the > retention of the EPROMs. It was not to fix random failures. > > It sounds like your EPROMs have various failures that wouldn't be helped by > baking. > > Each time the EPROM is programmed, there is a slight increase in the leakage > of the floating gate. This was typical after thousands of program/erase > cycles. Baking them repaired the damage to the insulating layer that was > damaged. > > Dwight > > > > From: cctalk on behalf of william degnan via > cctalk > Sent: Wednesday, December 13, 2017 6:18:16 AM > To: Mark G Thomas; General Discussion: On-Topic and Off-Topic Posts > Subject: Re: EPROM baking > > On Wed, Dec 13, 2017 at 9:08 AM, Mark G Thomas via cctalk < > cctalk@classiccmp.org> wrote: > > > Hi, > > > > I am working on several projects requiring 2708 and 2716 EPROMs, and > > am finding some of my chips will not erase, and some will not take > > a program. I've also learned more in the past week than I wanted > > to know about repairing Data-I/O 29a/b programmers. > > > > I vaguely remember in the 1990s baking such EPROMs in the oven, but > > I do not remember temperature or time. I was surprised that Google > > didn't turn up anything useful with this info. > > > > I'm sure someone here will have some notes on EPROM baking. > > > > Mark > > > > > > > > Mark, > > If this is an issue about reviving bad eproms? I assume you have tried the > regular stuff. > > What process are you using now to erase 2708/16's? I have a simple eraser > unit and it seems to always work. Some eproms go bad but I never have > issues with erasing them. My point is that maybe you need a better prom > eraser unit. I would avoid baking them until you have exhausted other > options. Not sure what others think. This topic has come up before here, > about putting them outside and all that. The erasers are all over ebay, > and the hardware store is full of the correct types of lighting, why not > make a box that will do the job?I assume there is more to it that > simply erasing them. > > > Bill -- Technik Service u. Handel Tiffe, www.tsht.de, Holm Tiffe, Freiberger Straße 42, 09600 Oberschöna, USt-Id: DE253710583 i...@tsht.de Fax +49 3731 74200 Tel +49 3731 74222 Mobil: 0172 8790 741
Re: EPROM baking
When I was at Intel, years ago, I recall the baking was only to repair the retention of the EPROMs. It was not to fix random failures. It sounds like your EPROMs have various failures that wouldn't be helped by baking. Each time the EPROM is programmed, there is a slight increase in the leakage of the floating gate. This was typical after thousands of program/erase cycles. Baking them repaired the damage to the insulating layer that was damaged. Dwight From: cctalk on behalf of william degnan via cctalk Sent: Wednesday, December 13, 2017 6:18:16 AM To: Mark G Thomas; General Discussion: On-Topic and Off-Topic Posts Subject: Re: EPROM baking On Wed, Dec 13, 2017 at 9:08 AM, Mark G Thomas via cctalk < cctalk@classiccmp.org> wrote: > Hi, > > I am working on several projects requiring 2708 and 2716 EPROMs, and > am finding some of my chips will not erase, and some will not take > a program. I've also learned more in the past week than I wanted > to know about repairing Data-I/O 29a/b programmers. > > I vaguely remember in the 1990s baking such EPROMs in the oven, but > I do not remember temperature or time. I was surprised that Google > didn't turn up anything useful with this info. > > I'm sure someone here will have some notes on EPROM baking. > > Mark > > > Mark, If this is an issue about reviving bad eproms? I assume you have tried the regular stuff. What process are you using now to erase 2708/16's? I have a simple eraser unit and it seems to always work. Some eproms go bad but I never have issues with erasing them. My point is that maybe you need a better prom eraser unit. I would avoid baking them until you have exhausted other options. Not sure what others think. This topic has come up before here, about putting them outside and all that. The erasers are all over ebay, and the hardware store is full of the correct types of lighting, why not make a box that will do the job?I assume there is more to it that simply erasing them. Bill
Re: EPROM baking
On Wed, Dec 13, 2017 at 9:08 AM, Mark G Thomas via cctalk < cctalk@classiccmp.org> wrote: > Hi, > > I am working on several projects requiring 2708 and 2716 EPROMs, and > am finding some of my chips will not erase, and some will not take > a program. I've also learned more in the past week than I wanted > to know about repairing Data-I/O 29a/b programmers. > > I vaguely remember in the 1990s baking such EPROMs in the oven, but > I do not remember temperature or time. I was surprised that Google > didn't turn up anything useful with this info. > > I'm sure someone here will have some notes on EPROM baking. > > Mark > > > Mark, If this is an issue about reviving bad eproms? I assume you have tried the regular stuff. What process are you using now to erase 2708/16's? I have a simple eraser unit and it seems to always work. Some eproms go bad but I never have issues with erasing them. My point is that maybe you need a better prom eraser unit. I would avoid baking them until you have exhausted other options. Not sure what others think. This topic has come up before here, about putting them outside and all that. The erasers are all over ebay, and the hardware store is full of the correct types of lighting, why not make a box that will do the job?I assume there is more to it that simply erasing them. Bill
EPROM baking
Hi, I am working on several projects requiring 2708 and 2716 EPROMs, and am finding some of my chips will not erase, and some will not take a program. I've also learned more in the past week than I wanted to know about repairing Data-I/O 29a/b programmers. I vaguely remember in the 1990s baking such EPROMs in the oven, but I do not remember temperature or time. I was surprised that Google didn't turn up anything useful with this info. I'm sure someone here will have some notes on EPROM baking. Mark -- Mark G. Thomas (m...@misty.com), KC3DRE
