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#4254225 TI and the MiniPro TL866 EPROM Programmer

Posted by atrax27407 on Mon Apr 8, 2019 8:54 PM

Did a search on eBay for the MiniPro TL866CS/A. The only auctions that I could find were obvious counterfeits. The manufacturers were variously listed as "Signetics",  Diymode" or "Unbranded, Generic". There were no listings for genuine units. So, if you don't already have a genuine TL866CS/A, you are now restricted to Vn 6.82. That version is fine for chips used on the TI.

#4250305 New Card to allow Speech Synth to go Into P-Box

Posted by atrax27407 on Tue Apr 2, 2019 5:52 PM

Try this email (Harald Glaab) for SNUG:



#4249702 Myarc Geneve 9640 cards for sale/repair

Posted by atrax27407 on Mon Apr 1, 2019 5:31 PM

I have a hard drive (I'll have to look for it) that you can have, Tim. Don't know if it works. If not you can use it for a door stop. I actually found two ST-251s if you are interested (or if anyone else is interested in one or both of them).

#4247105 Myarc 512 Gal's

Posted by atrax27407 on Thu Mar 28, 2019 6:17 PM

One of the problems with those boards was that the PAL equations were incorrect. As a result, the board was non-functional. Also, I believe there was a design flaw.

#4246416 Myarc 512 Gal's

Posted by atrax27407 on Wed Mar 27, 2019 4:35 PM

Here are some PAL/GAL cross reference tables.

Attached Files

#4246139 Myarc 512 Gal's

Posted by atrax27407 on Wed Mar 27, 2019 10:28 AM

If the PAL/GAL equations can be re-constructed, one could use WINCUPL or another similar utility to assemble the JEDEC files from them. I have the logic files for the CorCom FDC Rev A and some miscellaneous third-party PALs (i.e., QUEST RAMdisk).

#4246057 Myarc 512 Gal's

Posted by atrax27407 on Wed Mar 27, 2019 9:16 AM

Jim Fetzner and I have been discussing the possibility of establishing a PAL/GAL repository for JEDEC files for a couple of years. The problem is that Myarc and most CorComp cards have the PALs locked which means that they cannot be easily read. The only recourse is to reverse engineer the circuitry to reconstitute the equations to produce appropriate JEDEC files. Anyone in the mood to take on such a project? I think Jim has the JEDEC files for most of the TI cards.

#4244550 TI and the MiniPro TL866 EPROM Programmer

Posted by atrax27407 on Mon Mar 25, 2019 6:34 AM

TL866II (or plus) is now updated to Vn 8.33. Multiple new chips added.

#4241013 Geneve 9938 issue

Posted by atrax27407 on Tue Mar 19, 2019 10:31 AM

Maybe Jim Fetzner will chime in here. He can tell you what to look for in a genuine chip online.

#4240368 MRS CP/M OS for Foundation Z80 Card

Posted by atrax27407 on Mon Mar 18, 2019 9:51 AM

You might want to read the reviews in MICROpendium 12/84 and 3/85. They seem to indicate that the system disks are TI SSSD (90K) format. Without knowing exactly what the disk format used would be, it would be "hit or miss" as far as recovering any of the data. That being said, I have a 5.25" DSDD drive connected to my system that works fine. If you have no other option, I would be willing to look at the disks.

#4238643 TI and the MiniPro TL866 EPROM Programmer

Posted by atrax27407 on Fri Mar 15, 2019 11:22 AM

SEE-IC has 55 TL866CS eprommers listed on eBay. I don't know if they are original, authentic units or counterfeit. However, SEE-IC has proven to be reliable in the past as far as chips are concerned, Caveat Emptor. Contact the seller for details. I don't know if this is a new listing or a re-post of the one taken down earlier.



#4238011 TI and the MiniPro TL866 EPROM Programmer

Posted by atrax27407 on Thu Mar 14, 2019 12:38 PM

Not completely accurate - EPROMs have an encryption byte that, when set, renders them unreadable by an EPROM programmer. When they are erased, the encryption byte is also erased and the chip can be re-used. There is a way around the encrypted chip dilemma, however. Tony McGiovern wrote a program years ago that will do a non-destructive read of the DSR of a card or peripheral device "in situ".  All you need is the CRU address and the file length(which can be easily changed in the source code). It runs exclusively from F'WEB and saves a complete eprommable file to disk. In essence, you are indirectly reading the EPROM.

#4236510 Wanted Replacement PAL Chip CorComp FDC 1985 rev A U12

Posted by atrax27407 on Mon Mar 11, 2019 9:49 PM

FYI - the EPROMs are the standard CorComp EPROMs. They are not the MG upgrades.

#4233573 TI and the MiniPro TL866 EPROM Programmer

Posted by atrax27407 on Wed Mar 6, 2019 9:25 PM

The old 2716 (2K) EPROMS (NOT TMS2716 which is incompatible with other 2716s) are getting a bit difficult to find and can be relatively expensive. The Chinese "rogue" suppliers have them but they are usually trash. For example, I ordered five of them a while ago and four of the chips were counterfeit and would not program. There is however, a substitution that can be made. This tip comes courtesy of Jim Fetzner:


Replacing a 2716 with a 2732 EPROM
A 2732 EPROM is backwards compatible – almost pin for pin – with a 2716 EPROM. There are only minor differences between the two chips. Pin 20 on the 2732 is G*/VPP  and G* on the 2716. That means there is no problem between the two of them signal-wise. Pin 21 is A11 on the 2732 and Vpp on the 2716. Again, there are no problems there as well. The direct substitution is a “no brainer” as long as one only programs the first 2K of the 2732 chip since A11 is held low when in a circuit.
Both of the EPROMs are a 24-pin package and all of the other signals with the exception of those two pins are identical. Since you aren’t using the one address pin that is different, and it is always held low when in circuit, there won’t be any issues with it at all.
The only consideration is to set the program range of the 2732 as >0000 to >07FF (or 2K) before starting the programming procedure on the MiniPro . This will restrict all of the code to the first 2K of the 2732 and it will function as a 2716.

#4231105 Files from Gazoo's system

Posted by atrax27407 on Sun Mar 3, 2019 7:49 AM