Troubles with eBay part suppliers

[Richard Lewis]

I think I posted on this before but I'm finding that purchasing flash based CPLD's on eBay has a lot of "caveat emptor" applied. Of about 20 MAX7000 CPLDs I bought, only 2 had accessible JTAG pins. This implies that these chips are not NOS as claimed but were stripped from boards where the JTAG pins had been disabled. They can be re-enabled by erasing the flash however I don't have the equipment to do this. Theoretically I can use a ROM burner with a suitable QFP to DIP converter socket but the 2 burners I have don't have definitions for Altera chips (probably too old). Otherwise, have to find a surplus Altera Master Programmer. 

I surmise that the solution to this would be to devise my own circuit for erasing these chips. So far I haven't found a datasheet or specs on how this is done but will keep fishing. I suppose I should just stick to non-Flash based FPGA's instead. 

-Richard

[Greg Holdren]

Richard,

So there is a way (factory knowledge) to erase the whole device (re-enabling JTAG access) without using JTAG by toggling the pins?

Greg

[Bill Shen]

I also have had bad experiences buying EPM7xxxS parts from eBay vendors.  Many parts won't talk to the JTAG programmer similar to what you've experienced, but some parts also drew high current.  I think the parts that drew high current are just plain bad.  It is possible the parts that won't talk to the JTAG programmer have overridden the JTAG pins with other functions, or possibly they are not even EPM7xxxS parts.  Have you found documentation about how to restore JTAG functions?  Probably need high voltage on certain pin(s).

Nowadays I buy my EPM7xxxS from UTSource which seem quite dependable.

  Bill

PS, Make sure you have the 7000S parts, not 7000A nor 7000E nor 7000. 

[Richard Lewis]

Hi Bill,

Yes they are 7000S parts. I will only buy from US sources from now. One of them emitted blue smoke which meant it wasn't really a EPM part and was something random that had been relabeled. I was able to remove the labeling with IPA. 

With regard to erasing the flash memory (and thus restoring the JTAG pins) I've found references to a "Altera Master Programmer" and the actual programmer on eBay. It looks like it has a Centronics style parallel interface. There is also some scattered info here: AN 100 which references a "JAM Player" executable which when used with the master programmer can erase the chip. I think the PITA needle is pegged at 11, i.e. this is getting too hard. I'll resource them from someone reputable and will give UTSource a go. 

-Richard

[TonyD]

Yes, I think we have all found that buying IC's from eBay can be very hit and miss.

I recently bought a batch of 10x Winbond 27C512 EPROM's and found when programming them two failed and identified as different models. Whilst not a massive failure rate, still a nuisance.

We should compile and share a list of reputable suppliers, not just eBay, and those we should avoid like the plague. Can we make a message post sticky?


Tony

[Bill Shen]

I was surfing the Web looking for info to re-enable JTAG signals on EPM7000S devices, no luck, but I did run across couple comments that confirm EPM7000S devices are compatible to Atmel 1500A devices such that you can develop CPLD code on Altera Quartus (it is so much better than WinCUPL), convert the POF output to JEDEC format and use ATMISPv7 to program the equivalent Atmel 1500A device.  The following is a portion of the article from
http://avitech.com.au/?page_id=3195
--------------------------------------------------
Verilog on the ATF1508

It has been mentioned to me that an old version of Altera’s Quartus II software can be used to develop in Verilog or VHDL to target the Atmel ATF1508AS device.

The process is documented in Atmel’s Application Note 0916.

The main steps are:

    Download and install a version of Quartus II that supported the MAX7000 series (ie version 13.0 SP 1). Make sure you tick the box to download the MAX7000 device support.
    In Quartus, target the MAX7000 part that has 128 macrocells. I selected EPM7128SLC84-15. Do the pin assignments in Qartus, as if you were intended to use the Altera device.
    After compiling your design in Quartus, use Atmel’s “pof2jed” Windows utility to convert the .pof file (generated by Quartus) to a .jed file. Note it is important to set JTAG Mode to “On” (rather than “Auto”) and to rick “Enable TDI_PULLUP” and “Enable TMS_PULLUP”, to make sure the JTAG port remains enabled after the programmer operation is completed (so the device can later be re-programmed via the JTAG interface).
    Program the JEDEC file into the ATF1508AS via a JTAG programmer. Note that you won’t be able to use the Quartus II Programmer software (in comination with a USB Blaster) for this task. The Quartus II Programmer will see the Atmel ATF1508AS in the JTAG chain, but won’t allow a .JED file to be downloaded to it. Instead, you need to use the Atmel ATMISP7 programmer application (in Windows) in combination with the Atmel xxxx1150 JTAG programmer.

[Richard Lewis]

Seems the required ISP programmer is still available for $60. I just bought one from Mouser ATDH1150USB Oddly, people are trying to sell this on eBay for $200+ 

Will arrive on Friday so will report back if it worked or not. If it does you can send me your CPLD's and I can erase them for you. 

-Richard

[Richard Lewis]

Didn't think this through... Just bought a QFP44 to DIP44 adapter so I can erase the bare chips. However I should be able to test this on the various breakout boards I've built (that haven't worked).  

-Richard

[Bill Shen]

I think there are misunderstanding. I don't believe Atmel programmer can restore JTAG capability to Altera parts. It can only program Atmel parts. I'm saying you can design with Altera Quartus tool and then convert to Atmel programming files format with POF2JED to program Atmel parts. This allow you to buy Atmel parts that are readily available but design with much better Altera tools. The Altera parts that won't talk to JTAG programmer are still unresolved.

Bill

[Richard Lewis]

Yes, it appears I conflated the two. I bought it from mouser so the worst that can happen is I return it. I still need to figure out how to erase these 16 chips or chuck them in the bin. 

[Rick Policy]

Thanks for the tip and link concerning ATmel parts! Gives me a good option for MAX7000 parts, since I love Quartus tools, but equally loathe Atmels Prochip Designer and even worse WinCupl.

[Bill Shen]

Please share your experience using Quartus to design Atmel CPLD. I myself have plenty of Altera epm7000s parts and have had no experience with Atmel CPLD. I also don't have an Atmel programmer so I can only pass along what I've read but can't confirm whether the process actually work or not.
Bill

[Bill Shen]

I read a posting on 6502.org about re-enabling JTAG function on Atmel 150x CPLD.  Since Atmel's 150x are basically clones of EPM7xxxS, I thought the same method would also work on EPM7xxxS parts.  I'm happy to report that the "12V to OE" trick also restore JTAG function to EPM7064S.

I bought 10pcs EPM7064S on eBay and only 4 can be recognized by the USB blaster.  I set the non working EPM7064S aside but tried them again after reading this thread.  I used a board with no other connections other than the JTAG connections.  I connected a 1.8K resistor to OE (pin 44) and apply 5V first and then 12V.  JTAG programmer still does not recognize the device, but I went through the motion of programming it anyway with 12V applied.  For few parts need to be programmed with 12V several times.  Eventually (with 12V removed), the JTAG will recognize the device and proceed to program and verify OK.  I put the "reconditioned" EPM7064S in a functioning board and they all worked correctly.  This is great trick!
  Bill

[Greg Holdren]

Thanks for the info Bill. Do have a direct link to the 6502  forum post?

Can you provide more details? I'm going to take a stab here: So all 5V/ground pins are connected as well as full JTAG interface. 12V to OE pin via a ~1.8k resistor and then program as normal?

Thanks,

Greg

[Bill Shen]

Greg,
This is the link to 6502.org post:
http://forum.6502.org/viewtopic.php?f=10&t=4349&start=15#p77393

The setup is exactly as you've described: VCC & GND hooked up according to data sheet.  JTAG interface hooked up, but other I/O pins unconnected.  Power pin 44 (EPM7064S's OE) to 12V through a 1.8K resistor.  Power up 5V first, then power up 12V.  Try to program the device and do autodetect.  These operations will fail, but then remove the 12V and repeat the programming.  It should then program OK.  You may have to try this procedure several times.
  Bill

[Tom Storey]

There has been some recent discussion about this on the EEVblog forum. Some people are also working on ways to reset the security bit so that locked devices can be used again.

I tried out the pof2jed process and wrote it up in this thread:

https://www.eevblog.com/forum/fpga/atmel-atf150x-cpld-and-wincupl/

Long story short, it worked fine. Verilog targeted at an EPM7032 and converted to run on an ATF1502.

Takes a few more steps but at least you can use parts that can be purchased brand new and reasonably guaranteed to be 100% functional.

Maybe the only downside is you're limited to a max of 128 MC.

I still use WinCUPL and WinSIM and have become quite proficient with them. I liken it to assembly for hardware. :-)

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[Bill Shen]

I remembered reading that discussion when I was googling for re-enbling jtag.  The 12V to OE1 appears to enable JTAG, but security fuse is another wrinkle that I have not encountered, yet.  I found EPM7064S from UTSource to be quite reliable, but I did have problem with EPM7128SLC84.  I have to send part of the shipment back because they don't respond to JTAG.

I may also switch over to ATF1504AS instead of EPM7064S.  There are not that much price difference except I do need to buy a more expensive programmer for ATF150x.  I'll still design in Altera Quartus which has excellent schematic and verilog/HDL capabilities. 
  Bill