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InsaneMultitasker

Myarc cards for sale/repair tips

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I poked around in my PC files and found a few scans from my working notebook - from 2001. I will ask Swim for his opinion on sharing one or more images.

 

Back then I wasn't too concerned with "accuracy" or making them pretty, and most times I completed the upgrades from memory. I didn't start with a lot of experience. Later, I looked for ways to standardize the wire colors, trace routing, etc. Some of my notes contained intentional errors in event the information was shared without my knowledge. This was important to protect intellectual property, particularly after someone stole a few things from me at one of the TI Faire gatherings.

 

(For what its worth the chips are hard to come by and the programmers we've tried won't properly program the chips, so neither swim nor I have had much reason to pursue new installations. A shame, really. )

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Which chips do you need to be able to program, o Insane One? I may be able to help there. . .as I have a pretty wide range of programmers, both hobby and professional grade.

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Which chips do you need to be able to program, o Insane One? I may be able to help there. . .as I have a pretty wide range of programmers, both hobby and professional grade.

It is the Atmel 29c040. It is nigh impossible to find this specific chip, as most of those for sale (if at all) are actually the 29c040a variation, which is a different sector size than the 040. Add to that the programmers seem to mess up the chips during the programming cycle, or program them incorrectly. If there was a good source of comparable chips, like the Winbond variety or even the 29c040a, that could be programmed properly, I would consider digging into the PFM code to make it compatible.

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Ah yes--I bought several of the various compatible chips to test them a while back. Looks like I need to do some testing then. If you have a BIN file that I can use as a test load, please send it to me privately and I'll see what ensues.

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Here is my notebook sketch for PFM512. The scan is from 2001; it was probably drawn in the late 90s during the waning days of Cecure. When installing both the 384K memory upgrade (using a single 512K sram) and the PFM512, there might be one additional JMx jumper change. I'd have to think that through to be sure.

post-25764-0-95618900-1536443693_thumb.jpg

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FYI - The TL866CS lists the ATMEL 29C040 as supported as well as the ATMEL 29C040A. Also UTSOURCE has AT29C040s listed on eBay in various quantities. Disclaimer: I have never ordered from them and can't verify the quality of the chips they sell.

Edited by atrax27407

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Today I found and was able to successfully program an Atmel 29c040A with the GQ-4X. The same programmer will NOT program a 29c040 and seems to trash them in the process; I think the routine is trying to program the 040 as if it is a 040A. I've shared additional details with Ksarul for testing at his convenience.

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Today I found and was able to successfully program an Atmel 29c040A with the GQ-4X. The same programmer will NOT program a 29c040 and seems to trash them in the process; I think the routine is trying to program the 040 as if it is a 040A. I've shared additional details with Ksarul for testing at his convenience.

 

that's awesome.

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Since this device is programmed directly by the Geneve (once installed) it requires the 29 chip.

 

Okay, this is intriguing... can you elaborate on this function?

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Okay, this is intriguing... can you elaborate on this function?

the PFM512 mod, as depicted in post 80, installs a 512K flash chip in the place of the standard 16K EPROM. The modification requires installation/stacking of a 32-pin socket and some changes to properly communicate with the chip. The flash is divided into 8K for the system boot routine, 128K for the OS, and 360K to hold files that can be accessed as if they are on a ramdisk. The entire flash chip can be programmed by a few utilities written for the Geneve. I use the 'flashdisk' to hold my most often used assembler/editor/disk utilities.

 

Some of the German cards, like the HSGPL, also contain flash chips that can be updated directly within the system. Leveraging the smaller capacity chips like the 29c256 would have been nice for our peripheral cards back then.

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I successfully updated two of my Geneve programs to detect the product ID and program the 040 or 040a accordingly. Next I completed a program I started back in 1998 to load the OS into the PFM chip without the use of the CYA utility. As of this evening the Geneve is booting the 'current' MDOS 7.00 development build via the PFM512 flash device. I didn't even trash the chip during development ;)

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I successfully updated two of my Geneve programs to detect the product ID and program the 040 or 040a accordingly. Next I completed a program I started back in 1998 to load the OS into the PFM chip without the use of the CYA utility. As of this evening the Geneve is booting the 'current' MDOS 7.00 development build via the PFM512 flash device. I didn't even trash the chip during development ;)

 

That's some good progress!

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