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Shift registers, latches and GAL devices...

A

Apocalypse

Hey,

an other quite technical question.
Maybe I'm get old (or insane?) but for the life of me I can't get a simple function to work in a GAL device (GAL16V8, GAL18V10, GAL20V8 or GAL22V10).
Basically I'm using the GAL as registered thus pin 1 is CLOCK and pin 11 (for DIP20 devices) or 13 (DIP24 devices) is OE.
What I want to achieve is have one input (say pin 2) latched to one output (say pin 12):

o12.d = i2;

Then I want o12 to be shifted to the next pin (13) on the next clock:

o13.d = o12

The issue is both outputs follow i2 on the rising edge of the clock.

I'm sure it can be done since I have a PAL chip (PAL16R4) doing exactly that.

[EDIT]
Basically want to do that:

sequential-seq15.gif
 
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I can't really help but GAL's are super interesting, this guy here might hold a clue:

https://justanotherelectronicsblog.com/?p=458

[obviously I'm not trying to tell @Apocalypse this stuff lol, just thinking out loud...]

Basically GAL's were the first generation of CPLD's which have evolved into FPGA's. I just learned PAL devices are OTP (One Time Programmable) and GAL devices are reprogrammable (EEPROM).

GALasm is what he's using and a TL866II Plus, someone in the comments mentions using minipro to program in Linux

You see a lot of people putting a CPLD or FPGA on a little DIP conversion board and using them in place of 74xx and GAL's. (I think I read about @caius doing it but I also remember he likes to do more authentic stuff with SMT versions of the 74xx IC's).
 
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K0NAM1 said:
[obviously I'm not trying to tell @Apocalypse this stuff lol, just thinking out loud...]
Click to expand...
No worries.

I'm way past that, I've been using PALs, GALs and CPLD for a long time. The SDIP64 custom chip on S18 romboards I reproduced in a CPLD.

I've read as much as I could online, the documentation too, software help content, etc. Nothing worked.

Tried with WinCUPL, ABEL 5, OpalJr, ISPLever...
Also tried different brands (Atmel, Lattice, etc.) and type of PLD (16V8, 18V10, 20V8, 22V10) and nothing worked.
Tried to develop using text language or graphic editor. Didn't work...

:(
 
If it's true to say that you can do anything on a GAL that you can do on a PAL then it must be possible, no?
 
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