Re: Help needed please re possible loss of a Burroughs B7800 CPU
Hi Evan and others who might have been wondering, I managed to find out what happened to the Burroughs B7800 that was "under the stairs" at Monash university. The good news is that the interesting parts, namely the indicator panels, have been saved by the Monash Museum of Computing History. They also retrieved the VAX 11/780 that was there too, and it is now in storage.
RE: No XT-IDE users?
> Ali, > > Definitely post at VCF. Hargle (Jeff) is usually lurking around. > Krille has been active in the development of the newer BIOS versions > and might be able to lend some insight. > > I have an ancient Rev-1 XT-IDE that I use regularly, but that BIOS is > ancient so I have no experience with the error that you are seeing. > > > Mike Thanks Mike. I already started a thread over at VCF. Hopefully, the hive mind can help me figure it out. -Ali
Re: Z80 / Z84C Swap (Doh!)
Thanks for the input, gents.. Sigh.. and here I sit, yet again, with neither a logic analyzer nor a decent digital scope. Unless something comes up, looks like I'll have to do it the hard way, as usual - heh. At least the machine doesn't have a totally scrambled brain, with the correct CPU - so it will be easier to work through things, as I can at least partially communicate with the hardware if needed. Well, except for the lack of bootable media.. Anyone have a spare Z-80? Or some bootable media for the Osborne 1? I have a few CP/M machines here, but I don't think any of them can write media for the Osborne. Even so, I'd need a way to get the Oz disk images to the machine of choice.. and that's another huge hurdle. Help a brother out.. I need some bootstrap media!! ;-) On Mon, Aug 17, 2015 at 12:13 AM, tony duell wrote: > [Replacement Z80 in an Osborne] > > > > What I did learn is that Z-80 were made in CMOS versions, and the Z84C is > > one. > > > > So what did I most likely do, here? Hose the CPU for sure? Collateral > > damage on the board? Both / Neither? > > Most likely neither (unless you put the CPU in the wrong way round or > zapped > something with static -- CMOS _and_ NMOS parts can be damaged that way). > > If the CPU is fast enough for the clock speed in that machine then most > likely > a CMOS one will work without problems. > > My guess is that the missing CPU was not the only fault. You now have a > good > CPU but problems elsewhere (clock, ROM, RAM, support logic...). Time to > grab > the logic analyser :-) > > -tony >
MARCH's Straight 8 restoration notes
The RICM PDP-12 thread made me realize that I (nor I think David Gesswein) ever posted our PDP-8 notes here. (We did post a link to the Youtube video of the ceremony at VCF East.) Anyway, here are David's notes: http://www.pdp8.net/shows/vcfe15/slides/PDP-8_Restoration.html and also his exhibit notes here: http://www.pdp8.net/shows/vcfe15/vcfe15.shtml.
RE: Z80 / Z84C Swap (Doh!)
[Replacement Z80 in an Osborne] > What I did learn is that Z-80 were made in CMOS versions, and the Z84C is > one. > > So what did I most likely do, here? Hose the CPU for sure? Collateral > damage on the board? Both / Neither? Most likely neither (unless you put the CPU in the wrong way round or zapped something with static -- CMOS _and_ NMOS parts can be damaged that way). If the CPU is fast enough for the clock speed in that machine then most likely a CMOS one will work without problems. My guess is that the missing CPU was not the only fault. You now have a good CPU but problems elsewhere (clock, ROM, RAM, support logic...). Time to grab the logic analyser :-) -tony
Re: No XT-IDE users?
Ali, Definitely post at VCF. Hargle (Jeff) is usually lurking around. Krille has been active in the development of the newer BIOS versions and might be able to lend some insight. I have an ancient Rev-1 XT-IDE that I use regularly, but that BIOS is ancient so I have no experience with the error that you are seeing. Mike On Sun, Aug 16, 2015 at 7:57 PM, Ali wrote: > > Yes. > > > > Although I'm no longer welcome there I'd still > > recommend VCF as the place to go for PC-related > > questions (next to our Chuck (G) of course ;-) > > > > m > > Mike (and everyone else thanks) for the input. That is sort of my feeling > as well - this list is geared toward older/bigger systems vs. VCF. That is > not to say you don't learn lots of cool things here (which is why I stay > active on both sides) but I was hoping that aside from Chuck, Jeff and some > of the original designers would be active here as well. I can repost at VCF > in hopes of solving the issue. > > -Ali > >
Re: Z80 / Z84C Swap (Doh!)
On Sun, Aug 16, 2015 at 8:48 PM, drlegendre . wrote: > The Zilog P/N of the chip is "Z84C0008PEC", and it's further marked "Z80 > CPU" with a datecode of "8904" - April of 1989? Assuming that your Z84C00 is not damaged, I think there's one difference that might make it not work in a circuit that works with the NMOS Z80. The clock input signal of the Z80 CPU, either NMOS or CMOS, is *not* TTL-compatible, but rather has a Vihc min spec of Vcc-0.6V, which for a 5V supply is 4.4V. Back in the day, many Z80 system designers ignored that problem, and drove the Z80 clock input from a normal TTL gate, which was marginal at best since the TTL Voh min spec is only 2.4V. In practice, you could usually get away with that in a 2.5 MHz design (original Z80), but at 4 MHz or higher it tended to be noticeably unreliable. The Mostek Z80 databook gives suggested drive circuits; I imagine that the Zilog documentation must have also. Anyhow, even though the Vihc spec is the same for NMOS and CMOS, the NMOS part might better tolerate a clock input that didn't reach as high as the spec. The other thing that could do it is if the circuit might have been designed such that a Z80 with very short clock-to-signal delays wouldn't work. That would be bad design since the Z80 has never had a minimum spec for those delays, so in such a case even a 6 or 8 MHz NMOS part might not work.
RE: Z80 / Z84C Swap (Doh!)
There is a clear possibility that there are other problems in the unit than the CPU chip. Look at the signals on the buss to see if they all look proper. I'm suspecting something load on the buss. Dwight
Re: QIC-24 data analysis
On 8/16/2015 6:29 PM, Chuck Guzis wrote: > On 08/16/2015 03:20 PM, Jay Jaeger wrote: > >> One issue with the capstan idea, though, would be direction. >> Capstans really want to pull. Not very good a pushing. ;) So if >> you did that, and you wanted to direction operation (required if you >> can't stream the entire tape), then you'd need two sets of capstans >> like the big IBM and the like 7 and 9 track tape drives had. > > Or CDC... :) > > Or maybe just a tachometer and let the reel motors do the work. QIC > data is pretty much self-clocking (but for those HP 2-track drives). > Exactly. > Still mulling it over--the number of QIC cartridges I've had to handle > has gone down substantially over the years. > > --Chuck > >
RE: No XT-IDE users?
> Yes. > > Although I'm no longer welcome there I'd still > recommend VCF as the place to go for PC-related > questions (next to our Chuck (G) of course ;-) > > m Mike (and everyone else thanks) for the input. That is sort of my feeling as well - this list is geared toward older/bigger systems vs. VCF. That is not to say you don't learn lots of cool things here (which is why I stay active on both sides) but I was hoping that aside from Chuck, Jeff and some of the original designers would be active here as well. I can repost at VCF in hopes of solving the issue. -Ali
Re: Z80 / Z84C Swap (Doh!)
Howdy Eric, Always a pleasure to hear from you! The Zilog P/N of the chip is "Z84C0008PEC", and it's further marked "Z80 CPU" with a datecode of "8904" - April of 1989? In the interim, I've pulled that chip from the Osborne and replaced it with the 'proper' Z80 from a Timex / Sinclair 1000; I did not record its markings, other than to note that it was produced in late 82, if I recall. The system now behaves better, but issues remain as follows: Started up +sans-KB+, the machine made a slight 'chirp' and a clean display came up with a message to the effect of "Insert disk in drive A and press RETURN". I attached the KB and restarted the machine. This time, the display came up with the same message, but there was something going on with the video.. it was quite flicker-y, with (scanline?) artifacts cruising around the screen. I placed a disk in Drive A and upon pressing RETURN the display immediately stabilized and went into a loop printing "BOOT ERROR" on successive lines, eventually scrolling the original boot message off the top of the display. It did not seem to even attempt seeking the disk - and it behaves the same way, whether or not a disk is in Drive A. Tried this routine several times, with minor alterations, and always the same - straight to the BOOT ERROR scroll and no other activity in the drive. Drive LED was on in all cases. So it seems there's more to this, than just a missing CPU. Hopefully my ham-fisted use of the Z84C hasn't caused any other issues! Oh, and FWIW, the machine seems to have the 1.4 BIOS and the double-density daughtercard on the mainboard. On Sun, Aug 16, 2015 at 9:29 PM, Eric Smith wrote: > On Sun, Aug 16, 2015 at 6:20 PM, drlegendre . > wrote: > > What I did learn is that Z-80 were made in CMOS versions, and the Z84C is > > one. > > > > So what did I most likely do, here? Hose the CPU for sure? Collateral > > damage on the board? Both / Neither? > > Actually it's surprising that the CMOS Z80 didn't work. The CMOS parts > are intended to be a drop-in replacement for the NMOS; unless they > have an "L" suffix, they are 5V, with TTL-compatible input thresholds. > I've replaced NMOS Z80 parts with CMOS equivalents in a number of > systems without difficulty. >
Re: Z80 / Z84C Swap (Doh!)
On Sun, Aug 16, 2015 at 6:20 PM, drlegendre . wrote: > What I did learn is that Z-80 were made in CMOS versions, and the Z84C is > one. > > So what did I most likely do, here? Hose the CPU for sure? Collateral > damage on the board? Both / Neither? Actually it's surprising that the CMOS Z80 didn't work. The CMOS parts are intended to be a drop-in replacement for the NMOS; unless they have an "L" suffix, they are 5V, with TTL-compatible input thresholds. I've replaced NMOS Z80 parts with CMOS equivalents in a number of systems without difficulty.
Re: No XT-IDE users?
On 08/16/2015 06:18 PM, Steven Hirsch wrote: What is the "Chuck mod"? I'll try to make this brief (ha!). One of the problems with the original XTIDE is that the data bus on a regular ATA drive is 16 bits. (There used to be a mode that could be set to allow an ATA drive to support 8-bit transfers, but that's long gone from most drives, now almost solely present in the CF interface). So the XTIDE would latch half the 16-bit bus on a read and make it available at a different I/O address IIRC, 8 locations higher). Reading, therefore became a matter of issuing an IN al,dx instruction, storing the byte, then adjusting the address in dx (XCHG DX,some other register) and repeating for the rest of the 16-bit word, adjusting dx again back to the original and looping... I observed that if the addressing of the drive was slightly modified by swapping I/O address bits 0 and 2, one could put the two halves of the 16-bit register ad adjacent I/O addresses and let the 8088 (or V20) BIU handle the input as a word operation. This means that the entire read loop on an 8088 collapses to a "in ax,dx / stosw/ loop" three-instruction sequence. On a V20, it's even simpler "rep insw". The last I recall, writes couldn't use the BIU trick because of the way the latch clocked data to the drive. You can't win 'em all. At least it was no slower than the old way--and code tends to do far more reads than writes. Of course, this results in the other ATA registers being a little out of normal sequence, but that's a simple code change. --Chuck
Re: No XT-IDE users?
On Sun, 16 Aug 2015, Chuck Guzis wrote: On 08/16/2015 03:26 PM, Ali wrote: Wow, I know it's not a DEC PDP but I was hoping at least a few people used the darn thing. Would it be better if I post in VCF? Thanks for any input. -Ali Probably. I have both the original and the one (can't remember the name) with the CPLD on it. Both worked well for me--and I modified the original to juggle the addressing bits to make the "Chuck mod". What is the "Chuck mod"? --
Re: No XT-IDE users?
- Original Message - From: "Ali" To: "CCTalk Mailing List" Sent: Sunday, August 16, 2015 6:26 PM Subject: No XT-IDE users? Wow, I know it's not a DEC PDP but I was hoping at least a few people used the darn thing. Would it be better if I post in VCF? Thanks for any input. -Ali - Reply - Yes. Although I'm no longer welcome there I'd still recommend VCF as the place to go for PC-related questions (next to our Chuck (G) of course ;-) m
Re: No XT-IDE users?
Be fun to have identified controller for first ibm pc to demo it Sent from my Verizon Wireless 4G LTE smartphone Original message From: william degnan Date: 08/16/2015 4:31 PM (GMT-07:00) To: "General Discussion: On-Topic and Off-Topic Posts" Subject: Re: No XT-IDE users? I don't have a need for it, yet anyway Bill Degnan twitter: billdeg vintagecomputer.net On Aug 16, 2015 7:26 PM, "Chuck Guzis" wrote: > On 08/16/2015 03:26 PM, Ali wrote: > >> Wow, I know it's not a DEC PDP but I was hoping at least a few people >> used the darn thing. Would it be better if I post in VCF? Thanks for >> any input. -Ali >> > > Probably. I have both the original and the one (can't remember the name) > with the CPLD on it. Both worked well for me--and I modified the original > to juggle the addressing bits to make the "Chuck mod". > > I've always used my own version of the BIOS; I've always felt that the > more elaborate BIOSes, while interesting and reflecting a lot of work, were > unnecessarily complicated. > > I"ll help if I can, but I haven't played much with the thing in a couple > of years+. > > --Chuck > > > >
Z80 / Z84C Swap (Doh!)
As the proud owner of an NtM Osborne 1 computer, courtesy of our own Jules Richardson (and another list member), I made no delay in opening the case to install a missing CPU. Jules was kind enough to let me know about the missing part prior to handing the old girl over to me. I'm sure you've already figured out what happened - unaware that the Z84C series was CMOS, that's what went into the Osborne's CPU socket. The machine came to life with a garbage display and howling on-board beeper. Tried resetting it a few times, all I got was more and different noise & garbage. That's when I shut down and did some reading - initially, I thought it might be a clock speed issue - sometimes 'faster' chips won't run at slower clock rates. What I did learn is that Z-80 were made in CMOS versions, and the Z84C is one. So what did I most likely do, here? Hose the CPU for sure? Collateral damage on the board? Both / Neither? As ever, it's what you don't get, that gets you.
LPSXX-AD NIB
I found several of these while digging. Any interest? Please contact me off list. Paul
Re: No XT-IDE users?
I don't have a need for it, yet anyway Bill Degnan twitter: billdeg vintagecomputer.net On Aug 16, 2015 7:26 PM, "Chuck Guzis" wrote: > On 08/16/2015 03:26 PM, Ali wrote: > >> Wow, I know it's not a DEC PDP but I was hoping at least a few people >> used the darn thing. Would it be better if I post in VCF? Thanks for >> any input. -Ali >> > > Probably. I have both the original and the one (can't remember the name) > with the CPLD on it. Both worked well for me--and I modified the original > to juggle the addressing bits to make the "Chuck mod". > > I've always used my own version of the BIOS; I've always felt that the > more elaborate BIOSes, while interesting and reflecting a lot of work, were > unnecessarily complicated. > > I"ll help if I can, but I haven't played much with the thing in a couple > of years+. > > --Chuck > > > >
Re: QIC-24 data analysis
On 08/16/2015 03:20 PM, Jay Jaeger wrote: One issue with the capstan idea, though, would be direction. Capstans really want to pull. Not very good a pushing. ;) So if you did that, and you wanted to direction operation (required if you can't stream the entire tape), then you'd need two sets of capstans like the big IBM and the like 7 and 9 track tape drives had. Or CDC... :) Or maybe just a tachometer and let the reel motors do the work. QIC data is pretty much self-clocking (but for those HP 2-track drives). Still mulling it over--the number of QIC cartridges I've had to handle has gone down substantially over the years. --Chuck
Re: No XT-IDE users?
On 08/16/2015 03:26 PM, Ali wrote: Wow, I know it's not a DEC PDP but I was hoping at least a few people used the darn thing. Would it be better if I post in VCF? Thanks for any input. -Ali Probably. I have both the original and the one (can't remember the name) with the CPLD on it. Both worked well for me--and I modified the original to juggle the addressing bits to make the "Chuck mod". I've always used my own version of the BIOS; I've always felt that the more elaborate BIOSes, while interesting and reflecting a lot of work, were unnecessarily complicated. I"ll help if I can, but I haven't played much with the thing in a couple of years+. --Chuck
Re: No XT-IDE users?
-BEGIN PGP SIGNED MESSAGE- Hash: SHA512 Hi, I have used it yes, and I'm actually quite happy with it - it wasn't that hard for me to get the PCBs; I just uploaded them to one of the PCB prototyping services out there (forgot which one, it has been a while already, and brain cells get rusty) and piggy-backed on a friend's order at Farnell. I have mine in an IBM 5150 with a CF card and it works stable and smooth, and I'd certainly recommend it. My machine was retrofitted with an ST-412, which had passed away by the time the machine reached me and this provided to be a useful alternative. If I recall correctly I couldn't find the exact flash part mentioned in the BoM I had for my model, and I managed to swap it out with a similarly spec'ed (but higher capacity) model. Y. On 16/08/2015 23:26, Ali wrote: > Wow, I know it's not a DEC PDP but I was hoping at least a few > people used the darn thing. Would it be better if I post in VCF? > Thanks for any input. -Ali > -BEGIN PGP SIGNATURE- Comment: GPGTools - https://gpgtools.org iQEcBAEBCgAGBQJV0RtaAAoJEElyT3Tqk/Mc/joH/ip5mPRLy5zq9OTZNxOWZtJ/ d+2hS3XHjm1Qeb2O+xLd6caGZOjN6+KSgtkJTah4QIzGo1wevojO7cKvCKhM6MJ6 6QV1YWd9bnKvMGe53Tio2+YSx8J2ectqgfZykEqznvgQqB1Z8NVIRy2MfjI/KgGm W3sKhXj8zau2Nl8/PHubNZsaUAf4z5iTeQwBrvWxUv7gUGASMA9yucQD2WgDINHf 1Io9Dh+S9J7x6PXg77cOHkS8EB59R919qmsYcN6nz45EX9XsBUreFp+hJ+XvZdXB o1KjmOVEC+8W39DWkCg/0TbaZlWi6AS/WrR3GM810z/1iYxF/43yiiEfCBEHU7g= =N8Pf -END PGP SIGNATURE-
No XT-IDE users?
Wow, I know it's not a DEC PDP but I was hoping at least a few people used the darn thing. Would it be better if I post in VCF? Thanks for any input. -Ali
Re: QIC-24 data analysis
On 8/16/2015 3:22 PM, Chuck Guzis wrote: > On 08/16/2015 10:15 AM, Jay Jaeger wrote: >> > >> More likely, apply the technology used on some 9 Track drives: a little >> tension arm and then use servos to drive the supply and takeup reels, >> and an encoder (*not* driven) that measures speed (in place of the >> capstan on older drives). > > Maybe--I know the method--you see it on some Cipher drives and it's even > on my tape cleaning machine. A capstan-pinch roller, I think is no > worse and might actually help with wrinkled QIC tapes that have made a > mess inside of a QIC cartridge when their tension belts have rotted out. > > --Chuck > > One issue with the capstan idea, though, would be direction. Capstans really want to pull. Not very good a pushing. ;) So if you did that, and you wanted to direction operation (required if you can't stream the entire tape), then you'd need two sets of capstans like the big IBM and the like 7 and 9 track tape drives had.
Re: PDP-12 Restoration at the RICM
On 8/16/2015 9:00 AM, Michael Thompson wrote: > We did a lot more debugging on the TC12 LINCtape controller. > > We saw a 500ns glitch in the LMU MOTION signal that corresponded to a short > slowdown in tape speed. We will investigate this next week. > > We entered the LINC instruction to check a single block (0707) in the left > switches and a block number (0777-) in the right switches. When we > pressed the DO key it should go to that block on the LINCtape. With large > block numbers (07xx) and with the tape positioned half way through the tape > it worked OK. With lower block numbers it sometimes could not find the > block and searched back-and-forth on the tape. The logic analyzer showed > that the block numbers were correct in a sequence of several blocks, and > then it will read a bad block number. The TC12 would tell the TU55 to turn > around, it would read a good block number, realize that it was going the > wrong direction, and turn the tape around. It would then read a good block > number, and then a bad block number, and turn around. > Just a gut hunch, based on the symptoms. Could you have a bit pick or drop in the block number in the TC12? Given the behavior, one might bet on a bit pick. Perhaps intermittent. Second gut hunch is that it would be hard to see how the drive could cause this UNLESS the TC12 uses one side of the redundant tape channels in one direction, and the other side in the other direction. Will be interesting to hear what you really find. JRJ
Re: SCSI Tape to TAP utility
Thanks Al, I downloaded the assembler just in case. And to Chuck's point, it always felt like the MSDN distribution was a poorly documented, disorganized mess. I was not impressed. The old Turbo C and new Watcom C are available freely for DOS 16 bit and people say very good things of both. Marc > From: Chuck Guzis > >> On 08/14/2015 12:00 PM, Al Kossow wrote: >> >> last 16 bit compiler is visual C++ 1.52c >> >> also ran across MASM 8 >> >> https://www.microsoft.com/en-us/download/details.aspx?id=12654 >> >> if you need it > Schizophrenic MS labeling. The C++ suite is 1.52c, but the compiler > identifies itself as 8.00c. Crazy. > > --Chuck
Re: QIC-24 data analysis
On 08/16/2015 10:15 AM, Jay Jaeger wrote: More likely, apply the technology used on some 9 Track drives: a little tension arm and then use servos to drive the supply and takeup reels, and an encoder (*not* driven) that measures speed (in place of the capstan on older drives). Maybe--I know the method--you see it on some Cipher drives and it's even on my tape cleaning machine. A capstan-pinch roller, I think is no worse and might actually help with wrinkled QIC tapes that have made a mess inside of a QIC cartridge when their tension belts have rotted out. --Chuck
Re: Analog to Digital Converter
On 8/16/2015 8:24 AM, Al Kossow wrote: On 8/15/15 6:41 PM, Jon Elson wrote: DDC made a number of hybrid ADCs, but I've never seen one that was 3 x 4"! That's really big. Some of the Data Translation modules were that big. The normally had the block diagram / part number / and Data Translation silk screened on the top of them. ADAC made some big modules as well. DT boards were pretty common in Multibus and DEC versions. I remember the Data Translation modules, I think the one I'm dealing with is from the same era.
Re: Analog to Digital Converter
On 8/15/2015 12:40 PM, tony duell wrote: I have a number of laboratory instruments that are from the 1990 time frame. They produce digital data that is the digitized signal from a detector, the data can be from 512 to 65K samples long. The ADC used in these instruments is a 16bit 100ksample/sec design. The ADC is in a 3 by 4 inch metal box with a row of pins on each long edge. [...] What is inside the box? Is it a hybrid circuit? I came across somewhat similar looking ADC and DAC modules in an I2S image display system. These were flat metal cans with pins on the bottom, going into individual sockets on the PCB. In that case the can could be opened up quite easily (I think just a couple of points to unsolder. Inside was a PCB _stuffed_ with components, including several possibly custom metal-can ICs (in the case of the ADC I susect fast analogue comparators). Have you tried to open your module? It may not be potted. -tony The ADC module is difficult to get at, the instrument it is in is very heavy and sealed against moisture. I was hoping to get more of heads up before I go back in.
Re: Analog to Digital Converter
I believe that is true, it is a SAR type of ADC. That is an import piece of information there concerning reading the ADC too fast. Because I have one instrument that is working properly I can use that as a baseline to look at how fast the ADC is being pinged on. This gives me something to go on. On 8/16/2015 12:56 AM, dwight wrote: Most of these older module use successive approximation converters. If you read them too fast, you'll only get a partial conversion. A number of manufactures made these modules. Analog Devices, Harris, Beckman and several others. Dwight From: a...@p850ug1.demon.co.uk To: cct...@classiccmp.org Subject: RE: Analog to Digital Converter Date: Sat, 15 Aug 2015 16:40:40 + I have a number of laboratory instruments that are from the 1990 time frame. They produce digital data that is the digitized signal from a detector, the data can be from 512 to 65K samples long. The ADC used in these instruments is a 16bit 100ksample/sec design. The ADC is in a 3 by 4 inch metal box with a row of pins on each long edge. [...] What is inside the box? Is it a hybrid circuit? I came across somewhat similar looking ADC and DAC modules in an I2S image display system. These were flat metal cans with pins on the bottom, going into individual sockets on the PCB. In that case the can could be opened up quite easily (I think just a couple of points to unsolder. Inside was a PCB _stuffed_ with components, including several possibly custom metal-can ICs (in the case of the ADC I susect fast analogue comparators). Have you tried to open your module? It may not be potted. -tony
Re: Analog to Digital Converter
On 8/15/15 6:41 PM, Jon Elson wrote: DDC made a number of hybrid ADCs, but I've never seen one that was 3 x 4"! That's really big. Some of the Data Translation modules were that big. The normally had the block diagram / part number / and Data Translation silk screened on the top of them. ADAC made some big modules as well. DT boards were pretty common in Multibus and DEC versions.
Re: WANTED: HP 3000
On 8/15/2015 3:18 PM, couryho...@aol.com wrote: Mike - this would be a good complete system for you Mike and good it has tapes. that may have the little cartridge drive in it too but beware the cartridge drives they seem to all have gummy capstans... I ruined a fos tape put it in... got error... pulled it out and looked like it was slimed with the 'black oil' like in x files! there is a work around for this though using some glue and rings on the capstan roller after you scrape the goo off.having the large tape drive is better anyway. like this unit has. To be clear: The computer does not have a cartridge tape drive. The computer rack has the CPU and three shoebox drives. I believe each drive is about 330MB. The tape drive that I would add in the deal is a rackmount HP7980 AUTOLOADER. I think it is so cool to watch these drives load a tape. Almost magical how the tape winds it's way through the drive. See yas. Steve Robertson
Re: TSX Plus...
> > > > On Mon, Mar 3, 2014 at 8:11 PM, Lyle Bickley > > > wrote: > > > > > >> After stating that I expected TSX Plus to be available generally > > >> to the collector community this week, I have had a number of folks > > >> request access to TSX plus via private FTP. > > >> > > >> Please be a bit patient and wait for me to post it to a new > > >> website I'm in the process of creating. I now have full agreement > > >> from S&H to generally release TSX Plus, COBOL, etc., to the > > >> collector community via a simple download. > > >> > > > > > > After a bit of a hiatus with the PDP-11, I'm getting back into it. > > > Wondering if there's any update on this? Would be great to see the > > > TSX Plus bits and documentation you've collected, especially > > > considering your work with S&H to pave the way. > > > > > > > > > I am also very interested in this. > > Sorry guys, I dropped the ball on this. I've been doing a bunch of > transitioning and ended up working on a number of other projects - and > completely forgot about TSX. > > This discussion is prodding me to finish my half done website for TSX... > > I apologize for the huge delay... > > Lyle > > -- > Bickley Consulting West Inc. > http://bickleywest.com > > "Black holes are where God is dividing by zero" > Bump? I'm still quite interested in this (and if we can collect some other TSX Plus software as mentioned by other list members). - Earl
Re: PDP-12 Restoration at the RICM
We did a lot more debugging on the TC12 LINCtape controller. We saw a 500ns glitch in the LMU MOTION signal that corresponded to a short slowdown in tape speed. We will investigate this next week. We entered the LINC instruction to check a single block (0707) in the left switches and a block number (0777-) in the right switches. When we pressed the DO key it should go to that block on the LINCtape. With large block numbers (07xx) and with the tape positioned half way through the tape it worked OK. With lower block numbers it sometimes could not find the block and searched back-and-forth on the tape. The logic analyzer showed that the block numbers were correct in a sequence of several blocks, and then it will read a bad block number. The TC12 would tell the TU55 to turn around, it would read a good block number, realize that it was going the wrong direction, and turn the tape around. It would then read a good block number, and then a bad block number, and turn around. At this point we don't think that we are working with bad tapes, but the problem might be in either the TU56 tape drive, or the TC12 LINCtape controller. We see bad behavior in both devices so we will do as Charles Lasner suggested and swap a TU55 and TU56 between the PDP-12 and the PDP-8/I. This will let us test the TU56 with a known good TC01 LINCtape controller, and test a known good TU55 with a questionable TC12 LINCtape controller. We ran the A-to-D converter test and were rewarded with a display on the VR14 that showed correct operation of the knobs and A-to-D converters. -- Michael Thompson
Re: WANTED: HP 3000
Hi Mike, Sorry I no longer have any HP3000 gear, but have did make several videos about my 3000s when I did. You can see them here: https://www.youtube.com/user/CLCourtney/videos Good luck - the 3000 was a great minicomputer in its day! Lee C. On Fri, Aug 14, 2015 at 7:01 PM, Mike Loewen wrote: > >I worked on HP 3000 systems in the late '80s, and would like to find > one for my collection. A series 42 would be nice, but a series 37 or micro > XE would do. Any leads? I'm already aware of the one on Epay in Florida > that's been sitting at $1,725 for the past year. > >I'm in central PA. > > > Mike Loewen mloe...@cpumagic.scol.pa.us > Old Technology http://q7.neurotica.com/Oldtech/ > -- Lee Courtney +1-650-704-3934 cell
Re: QIC-24 data analysis
On 8/16/2015 11:19 AM, Chuck Guzis wrote: > On 08/16/2015 08:24 AM, dwight wrote: >> I left a note there about using CRCs to do data correction. It is a >> simpler method for software than normally use. > > I posted a link on VCF about using GNU CRC RevEng--a great little > utility to aid in determining polynomials and initial conditions for > CRCs. Not too different from figuring oddball floppy encodings. > > What I'd like to see is a QIC mechanical solution that treats DC carts > as a reel-to-teel drive--no tension band worries. I imagine this could > be done by motorizing the takeup and supply reels and putting in a > driven capstan with suitable RPM control. Head positioning, of course, > could be handled the normal way. Perhaps an old top-of-the-line audio > cassette transport could be adapted. > > --Chuck > More likely, apply the technology used on some 9 Track drives: a little tension arm and then use servos to drive the supply and takeup reels, and an encoder (*not* driven) that measures speed (in place of the capstan on older drives).
Re: Shugart 800-8 media centering problem
I'd always wondered why that was so.It has been handy to see which were 360K as I don't think HD everhad the donut ( maybe rare ).Dwight On Sun, 16 Aug 2015, Chuck Guzis wrote: Where I saw the problem was with the Micropolis 77-track (single sided) 100 tpi drives. Their 35 track 48tpi ss drive was the same. Exceptionally sturdy and reliable drive, but not much slope on that cone, and the helical lead screw wasn't intended to step very fast. Hub reinforcers were on the later 300 Oersted disks. OR user added to early 300s and to 600 Oersteds. A disk without a hub ring could be either an early 360K or a 1.2M So, they weren't an especially reliable way to identify disks. Adding hub rings to 8" disks made for fewer issues for centering. IFF installed right - an off-center hub ring makes for even more fun.
Re: Shugart 800-8 media centering problem
On 08/16/2015 08:46 AM, dwight wrote: I'd always wondered why that was so.It has been handy to see which were 360K as I don't think HD everhad the donut ( maybe rare ).Dwight Where I saw the problem was with the Micropolis 77-track (single sided) 100 tpi drives. --Chuck
Re: QIC-24 data analysis
On 08/16/2015 08:24 AM, dwight wrote: I left a note there about using CRCs to do data correction. It is a simpler method for software than normally use. I posted a link on VCF about using GNU CRC RevEng--a great little utility to aid in determining polynomials and initial conditions for CRCs. Not too different from figuring oddball floppy encodings. What I'd like to see is a QIC mechanical solution that treats DC carts as a reel-to-teel drive--no tension band worries. I imagine this could be done by motorizing the takeup and supply reels and putting in a driven capstan with suitable RPM control. Head positioning, of course, could be handled the normal way. Perhaps an old top-of-the-line audio cassette transport could be adapted. --Chuck
RE: Shugart 800-8 media centering problem
> From: ccl...@sydex.com snip > I believe that the earlier Micropolis 5.25" floppy drives worked the > same way. I recall that when they first came out, they'd mangle the hub > area of a floppy because the spindle motor often had been turned off by > the host. Eventually, the design was modified so that the motor spun up > as the drive door closed, which solved the problem. > > Before that, Dysan had experimented with putting a reinforcing ring on > their floppies. By the time high-density drives came out, the problem > had been solved so there was no need to reinforce the HD floppy hub area. > > --Chuck > > I'd always wondered why that was so.It has been handy to see which were 360K as I don't think HD everhad the donut ( maybe rare ).Dwight
RE: QIC-24 data analysis
I left a note there about using CRCs to do data correction. It is a simpler method for software than normally use. Dwight > Date: Sat, 15 Aug 2015 07:24:24 -0700 > From: a...@bitsavers.org > To: gene...@classiccmp.org; classiccmp.org:On-Topic and Off-Topic Posts > cctalk@classiccmp.org > Subject: QIC-24 data analysis > > > This looks like fun.. > > http://mightyframe.blogspot.com/2015/08/qic-24-tape-data-block-format-decoding.html >
RE: Analog to Digital Converter
I was thinking that around this time, dual slop detectors were becoming popular but it is unlikely this is your problem. If reading a dual slope before conversion is complete, the value read would be low in value, not just missing LSBs. They were generally slower as well but often in the 16 or more bits of accuracy. Tinker Dwight
RE: Analog to Digital Converter
At 12:56 AM 8/16/2015, Dwight wrote: >Most of these older module use successive approximation converters. If you >read them too fast, you'll only get a partial conversion. I'll second that. The ones I have seen most often (in another industry) were Harris. For those who would like who would like to increase their understanding of DSP I suggest: http://what-when-how.com/Tutorial/topic-3062l7iib/Applications-of-DSP-to-Audio-and-Acoustics-113.html For greater background on and history of DSP I suggest looking up some of the references cited in that paper if you have access to a good EE library. Dale H. Cook, Roanoke/Lynchburg, VA Osborne 1 / Kaypro 4-84 / Kaypro 1 / Amstrad PPC-640 http://plymouthcolony.net/starcity/radios/index.html
Re: Clearpoint DCME/Q4E configuration
On 2015-08-16 02:52, Noel Chiappa wrote: Hi, does anyone know anything about the configuration of these boards? (The document on BitSavers only covers the Q4B; the jumper configuration on the Q4E is totally different.) They are 4MB quad QBUS memory cards; PMI capable, I'm pretty sure. I have two of them, one of which came out of an 11/84 (I never saw it in the machine, though), and is so probably configured to run PMI. The thing is that I stupidly mixed it in with the other one, and now I don't know which one is which - and they are jumpered differently. It doesn't have to be full (or any) documentation; if someone had one they _knew_ was jumpered for, say, PMI operation, I could copy their jumper setup (or see if one of mine already had the same). If not, I'm going to start in on drawing a picture of all the jumpers, and see what QBUS/PMI pins they are all connected to - looking at the card, there's a big row of jumpers next to the pins the PMI is on, and the jumpers are all 'on' on one card, and all 'off' on the other, so I suspect the one card is jumpered for PMI operation, and the other, not. So, even if there no documentation extant at all, we should be able to more of less figure out what many of the jumpers do, and start making use of these cards. But any help/info would be gratefully received! Not a direct help, but DEC's memory boards never had any jumpers for PMI as such. It was automatically detected depending on where the board was placed on the backplane. Jumpers/switches were only used to set the base address and the CSR address of the boards. Johnny -- Johnny Billquist || "I'm on a bus || on a psychedelic trip email: b...@softjar.se || Reading murder books pdp is alive! || tryin' to stay hip" - B. Idol
Still more Parts available: DEC, TI-990, and HP1000
I've just added to yesterday's list of vintage computer items that need to find a good home. Details, part numbers, and descriptions can be found here: http://www.hpfriedrichs.com/hpfparts/hpfparts.htm Thank you to several classiccmp members who corrected my earlier post. Some of the parts I have listed are associated with PDP 11/23s, not 11/34s. 73 Pete AC7ZL
Re: Analog to Digital Converter
On 08/15/2015 11:18 AM, Douglas Taylor wrote: I have a number of laboratory instruments that are from the 1990 time frame. They produce digital data that is the digitized signal from a detector, the data can be from 512 to 65K samples long. The ADC used in these instruments is a 16bit 100ksample/sec design. The ADC is in a 3 by 4 inch metal box with a row of pins on each long edge. I think some of them are failing because I get the full 16 bit resolution from one machine, but not the others. This was determined by taking the digital samples and sorting the values and computing the increments between the adjacent values. In some cases the output looked like 14 bit resolution and in one case 6 bit resolution. Does anyone have any experience with technology? Who was the manufacturer? (There is no id on the outside) What is inside the box? Is it a hybrid circuit? DDC made a number of hybrid ADCs, but I've never seen one that was 3 x 4"! That's really big. Most likely there is a normal PC board inside, with a bunch of chips and discrete components on it. Is this box hermetic, or maybe if you peel back a label, there may be screws that hold it together. Jon
RE: Analog to Digital Converter
Most of these older module use successive approximation converters. If you read them too fast, you'll only get a partial conversion. A number of manufactures made these modules. Analog Devices, Harris, Beckman and several others. Dwight > From: a...@p850ug1.demon.co.uk > To: cct...@classiccmp.org > Subject: RE: Analog to Digital Converter > Date: Sat, 15 Aug 2015 16:40:40 + > > > > I have a number of laboratory instruments that are from the 1990 time > > frame. They produce digital data that is the digitized signal from a > > detector, the data can be from 512 to 65K samples long. The ADC used in > > these instruments is a 16bit 100ksample/sec design. The ADC is in a 3 > > by 4 inch metal box with a row of pins on each long edge. > > [...] > > > What is inside the box? Is it a hybrid circuit? > > I came across somewhat similar looking ADC and DAC modules in an I2S image > display system. These were flat metal cans with pins on the bottom, going into > individual sockets on the PCB. > > In that case the can could be opened up quite easily (I think just a couple > of points > to unsolder. Inside was a PCB _stuffed_ with components, including several > possibly > custom metal-can ICs (in the case of the ADC I susect fast analogue > comparators). > > Have you tried to open your module? It may not be potted. > > -tony
RE: Analog to Digital Converter
> I have a number of laboratory instruments that are from the 1990 time > frame. They produce digital data that is the digitized signal from a > detector, the data can be from 512 to 65K samples long. The ADC used in > these instruments is a 16bit 100ksample/sec design. The ADC is in a 3 > by 4 inch metal box with a row of pins on each long edge. [...] > What is inside the box? Is it a hybrid circuit? I came across somewhat similar looking ADC and DAC modules in an I2S image display system. These were flat metal cans with pins on the bottom, going into individual sockets on the PCB. In that case the can could be opened up quite easily (I think just a couple of points to unsolder. Inside was a PCB _stuffed_ with components, including several possibly custom metal-can ICs (in the case of the ADC I susect fast analogue comparators). Have you tried to open your module? It may not be potted. -tony
Re: docs or software for Quay 900 (uses Quay 90F/MPS board)
I just realized that the toggling of pin 14 is thanks to the feature of the uPD765/8272 that automatically polls all four drives. I mostly have worked with WD controllers which don't do that. So I still don't know why the TWOSIDED/ signal isn't being reflected in ST3. I'll have to trace out how it's wired on the board.
Re: docs or software for Quay 900 (uses Quay 90F/MPS board)
My references to pin 14 should have been to pin 10 for the TWOSIDED/ signal. Pin 14 is the SIDESELECT/ signal which was working fine.
