[XCSSA] 16R8 burner?

Fri, 12 Aug 2005 10:57:42 -0500

On Aug 11, 2005, at 9:50 PM, xcssa-admin@xcssa.org wrote:

> Does anyone have or know about burners for 16R8 chips?  I may need  
> to replace a broken 16V8B, and I've been told 16R8 is the  
> replacement chip family.

You've got it backwards.  16R8 is one model of the old-fashioned and  
long obsolete fuse PAL chips, while the 16V8 is a more modern EEPROM- 
based GAL chip.  The 16V8, 20V8, and 22V10 (which are now 15-year old  
technology) were designed to replace dozens of different models of  
PAL chips.  It was absurd how many models of PAL chips there were.

However they are all programmable chips, just like EPROMs, so you  
have to have to have something to burn onto them.  And their  
programming information is not interchangeable, as each has a  
different arrangement of fuses and output logic.  The old fuse PAL  
fusemaps can be translated for GALs with a properly written program  
(good luck trying to find one), or by reverse engineering.

If you know what the logic equations are, I could probably come up  
with a 16V8 fusemap for it and even burn a chip.

As for actually burning them, all modern burners that have PLD  
(programmable logic device) support will burn GAL chips, but if you  
need to read an old PAL chip, you might be out of luck.  The best  
option is probably to find a BP Microsystems CP-1132 on ebay, which  
is nice because it can also do EPROMs.  All you need is a real (non- 
PCI) parallel port and any version of Winderz.  I also have a spare  
PLD-only version that I would be willing to get rid of cheap now that  
I have a CP-1132, but it's under stuff and I'd have to dig for it.

Too bad there wasn't any time for me to talk last month, or I would  
have talked about PAL and GAL chips.  For now, you can read these for  
a crash course on PLDs:

http://www.ddpp.com/DDPP3_mkt/c05samp1.pdf
http://www.ddpp.com/DDPP3_mkt/c08samp2.pdf

(go to the parent directory and there's still a lot of good  
information in there considering they're sample pages from a textbook)

  - Bruce -