Re: Old MOS Mask-Programmed ROM forgetfulness?

I was about ready to recommend the same approach. Speed is not the issue. Then when if the time ever comes to replace the part one could if have to build a board to do any level/timing shifts. A solution I've used before. On Wed, Feb 17, 2016 at 5:52 PM, Rick Bensene wrote:

RE: Old MOS Mask-Programmed ROM forgetfulness?

Brent Hilpert wrote: > Apparently there actually is an equivalent EPROM, according to this > datasheet for the MM4203/MM5203 EPROM: > http://www.datasheetarchive.com/dl/Scans-006/Scans- > 00137265.pdf > > It states they are pin-compatible to the MM5213/MM5231 mask ROMs. > The EPROM even

Re: Old MOS Mask-Programmed ROM forgetfulness?

On Tue, Feb 16, 2016 at 12:06 PM, Brent Hilpert wrote: > Apparently there actually is an equivalent EPROM, according to this > datasheet for the MM4203/MM5203 EPROM: > http://www.datasheetarchive.com/dl/Scans-006/Scans-00137265.pdf > > It states they are pin-compatible

Re: Old MOS Mask-Programmed ROM forgetfulness?

On 02/16/2016 12:43 PM, dwight wrote: It is interesting, I have 1702As that were programmed in 1973 sometime and they still have their data ( used on my SIM4-01 ). And yes, I have them backed up. It is interesting that Data I/O has added supply current checks. I've used many home made pin

Re: Old MOS Mask-Programmed ROM forgetfulness?

a typical adapter together. Dwight From: cctalk <cctalk-boun...@classiccmp.org> on behalf of Brent Hilpert <hilp...@cs.ubc.ca> Sent: Tuesday, February 16, 2016 11:06 AM To: General Discussion: On-Topic and Off-Topic Posts Subject: Re: Old MOS Mas

Re: Old MOS Mask-Programmed ROM forgetfulness?

On 2016-Feb-15, at 11:25 PM, Eric Smith wrote: > On Mon, Feb 15, 2016 at 11:31 PM, John Robertson wrote: >> Rick, if you want to archive these PROMs (highly recommended) you should be >> able to find a Data I/O 29B and get one of the programming packs that >> supports NS chips.

Re: Old MOS Mask-Programmed ROM forgetfulness?

Rick Bensene wrote: > Hi, all, > > I have a question about old Mask-Programmed ROMs > > The part in question is the National Semiconductor MM5231. This part is > a 2K-bit PMOS Mask-Programmed ROM, generally organized as 256x8, but > also can be organized (via a MODE pin)as 512x4 bits. In this

Re: Old MOS Mask-Programmed ROM forgetfulness?

On 02/15/2016 11:25 PM, Eric Smith wrote: On Mon, Feb 15, 2016 at 11:31 PM, John Robertson wrote: Rick, if you want to archive these PROMs (highly recommended) you should be able to find a Data I/O 29B and get one of the programming packs that supports NS chips. I may have

Re: Old MOS Mask-Programmed ROM forgetfulness?

On Mon, Feb 15, 2016 at 11:31 PM, John Robertson wrote: > Rick, if you want to archive these PROMs (highly recommended) you should be > able to find a Data I/O 29B and get one of the programming packs that > supports NS chips. I may have such a combination in my collection, but

Re: Old MOS Mask-Programmed ROM forgetfulness?

On 02/15/2016 10:25 AM, Rick Bensene wrote: Hi, all, I have a question about old Mask-Programmed ROMs The part in question is the National Semiconductor MM5231. This part is a 2K-bit PMOS Mask-Programmed ROM, generally organized as 256x8, but also can be organized (via a MODE pin)as 512x4

Re: Old MOS Mask-Programmed ROM forgetfulness?

The ones you have to watch out for as a rule are those made by Mostek. Not sure of the date when they changed to recipe. If your still in/near PDX I will be getting my Unisite+ back in March and I may have a working Model 29 that you can borrow. -pete On Mon, Feb 15, 2016 at 10:25 AM, Rick

Old MOS Mask-Programmed ROM forgetfulness?

Hi, all, I have a question about old Mask-Programmed ROMs The part in question is the National Semiconductor MM5231. This part is a 2K-bit PMOS Mask-Programmed ROM, generally organized as 256x8, but also can be organized (via a MODE pin)as 512x4 bits. In this particular application, the parts