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Re: [N8VEM-S100:2870] Help Programming PAL's/GAL's

I really like the idea of using devices like this to simplify some of the S-100 boards.  

One suggestion I would have - the "traditional" PALs and the GALs (which can be configured in the same way as several different series of PALs, there is a useful note about that in the Jameco .PDF catalog) are pretty power hungry - the ones that Jameco carries have Icc around 140 mA vs many 74LS series ICs are around 30 mA.  Also if you look at other sources beyond Jameco like Digikey, those parts seem to no longer be in readily available stock anymore.

Atmel makes an "ATF" series which has Icc from 20mA to 55 mA - http://www.atmel.com/Images/doc0364.pdf.  The 20 mA version is $2.09 at Digikey (ATF16V8BQL-15PU-ND) and the 55 mA version is $1.69 (ATF16V8B-15PU-ND).

Also Atmel has free design software at http://www.atmel.com/tools/wincupl.aspx which runs in Windows and supports all the features of the devices.

If you're looking for a 16V8-type device I think these would be a good option in terms of being a currently available part with low power consumption and the design tool to match.  Something that any other builder could work with easily.  Not that the fuse links in GALs should be difficult, I have seen worked examples of doing it by hand, but it is a little bit of a lost art.


On Saturday, March 22, 2014 1:35:38 PM UTC-7, monahanz wrote:
Very interesting Rob!
AMD calls their GALS PALCExxx.  Looking at the pinouts, the NS, AMD and Lattice PAL and GAL 16V8's all look the same.

But based on your observation I set the Wellon VP-290 to think it was programming National Semi GAL's and would you believe it programmed OK!   Interestingly, if I add the "verify" option,  it fails to program correctly.  But at least the pins in hardware behave as expected.  Clearly a very simple set of equations, will obviously have to do more.

But I may have a solution, thanks for the pointer.
Will also see what Wellon says (they are quite helpful with e-mails BTW).


-----Original Message-----
From: n8ve...@googlegroups.com [mailto:n8vem...@googlegroups.com] On Behalf Of Rob Doyle
Sent: Saturday, March 22, 2014 11:54 AM
To: n8ve...@googlegroups.com
Subject: Re: [N8VEM-S100:2870] Help Programming PAL's/GAL's

On 3/21/2014 9:31 PM, monahanz wrote:

> Has anybody in this group had experience in the past programming
> simple GAL’s.

I helped some of the folks recreating the Heathkit H89 with more modern parts a few months ago.

The original H89 used fusable link PROMs as decoders - which are mostly unobtainable or expensive. I redesigned the logic so that we could use a bunch of GAL16V8s.

I uses the PALASM4 Ver 1.5 from:


I also used DOSBOX.

I don't see anything wrong with your design.

I don't think PALASM4 supports GALS. Somehow the person that built the board converted from 16L8 format to 16V8 format.

I wouldn't assume that a .JED file for a 16L8 would work with a 16V8.
The JED file is a fusemap.

Also different manufacturers have different programming algorithms.

What part are you using, exactly?


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