Shift registers, latches and GAL devices...

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    • Shift registers, latches and GAL devices...

      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:

      Looking for:
      - faulty Hang-On, Space Harrier or Enduro Racer (2203 sound board)
      - Sega Mega-CD 1 power board
      - Super Nintendo CPU (3 needed)



      "I'd 1cc games but I have a real life."
      01010011 01000101 01000011 01010010 01000101 01010100 00100000 01001101 01000101 01001110 01010101 00100000 01000111 01010101 01011001

      The post was edited 1 time, last by Apocalypse ().

    • No one?
      Looking for:
      - faulty Hang-On, Space Harrier or Enduro Racer (2203 sound board)
      - Sega Mega-CD 1 power board
      - Super Nintendo CPU (3 needed)



      "I'd 1cc games but I have a real life."
      01010011 01000101 01000011 01010010 01000101 01010100 00100000 01001101 01000101 01001110 01010101 00100000 01000111 01010101 01011001
    • New

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

      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).
      My VAPS

      Looking for genuine Konami classic PCBs, especially:

      Hyper SportsJail BreakJuno FirstMikiePandora's Palace
      Ping PongRoad FighterRush'N AttackTime Pilot '84Tutankham

      The post was edited 5 times, last by K0NAM1 ().

    • New

      K0NAM1 wrote:

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

      :(
      Looking for:
      - faulty Hang-On, Space Harrier or Enduro Racer (2203 sound board)
      - Sega Mega-CD 1 power board
      - Super Nintendo CPU (3 needed)



      "I'd 1cc games but I have a real life."
      01010011 01000101 01000011 01010010 01000101 01010100 00100000 01001101 01000101 01001110 01010101 00100000 01000111 01010101 01011001
    • New

      I found this:

      eevblog.com/forum/microcontrollers/pal16l8-pal16r4-gal16v8b/

      If that doesn't help and nobody chimes up here then EEVBlog would be a great place to ask... PCB.Wiz, TK & up8051 from what they're saying know this stuff and they were all active in the forums in the last 24 hours...
      My VAPS

      Looking for genuine Konami classic PCBs, especially:

      Hyper SportsJail BreakJuno FirstMikiePandora's Palace
      Ping PongRoad FighterRush'N AttackTime Pilot '84Tutankham

      The post was edited 1 time, last by K0NAM1 ().

    • New

      K0NAM1 wrote:

      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?
      Yes it should be, that's really making me mad.
      Looking for:
      - faulty Hang-On, Space Harrier or Enduro Racer (2203 sound board)
      - Sega Mega-CD 1 power board
      - Super Nintendo CPU (3 needed)



      "I'd 1cc games but I have a real life."
      01010011 01000101 01000011 01010010 01000101 01010100 00100000 01001101 01000101 01001110 01010101 00100000 01000111 01010101 01011001
    • New

      K0NAM1 wrote:

      I found this:

      eevblog.com/forum/microcontrollers/pal16l8-pal16r4-gal16v8b/

      If that doesn't help and nobody chimes up here then EEVBlog would be a great place to ask... PCB.Wiz, TK & up8051 from what they're saying know this stuff and they were all active in the forums in the last 24 hours...
      I guess I need to register there.
      Thanks for the tip.
      Looking for:
      - faulty Hang-On, Space Harrier or Enduro Racer (2203 sound board)
      - Sega Mega-CD 1 power board
      - Super Nintendo CPU (3 needed)



      "I'd 1cc games but I have a real life."
      01010011 01000101 01000011 01010010 01000101 01010100 00100000 01001101 01000101 01001110 01010101 00100000 01000111 01010101 01011001