2023年10月25日 · The Programmable Logic Array (PLA) is a hardware programmable chip in the C64 which only contains combinatorial logic. Designed by Dave DiOrio, the PLA is used to create chip select signals received from various other signals.

2020年7月16日 · Fully assembled and tested XCPLA, ready to install. Gorgeous, isn’t it? So you’ve determined your PLA is faulty and you’ve decided to pick up an XCPLA or similar replacement. Now comes the question, how do you install it?

The PLA is a design from scratch based on Thomas Giesel's excellent "The C64 PLA dissected" document. How good is it? Pretty good. Allthough I was amining at low-cost easy to build PLA, rather than building the best PLA in the world, the PLA has until now passed everything thrown at it.

2022年1月22日 · A C64 faulty PLA. A faulty PLA in a Commodore 64 computer can cause: blank (or black) screens, no borders, colored screens or flashing color garbage instead of startup screen, intermittent loss of the cursor, screen freeze and/or program crashes after warmup or random characters on screen.

PLA replacement circuit for Commodore 64. Based on dodgyPLA https://github.com/desaster/c64-dodgypla. I showed the design to some friends and they said "neat". Hence the name neatPLA …

The PLA or Programmable Logic Array is a computer chip that handles the memory map and the bank switching of the Commodore 64. Along comes Daniël Mantione who designed this handy device to replace the original PLA chip compatible in most Commodore 64 computers.

2020年11月21日 · You need two chips to make a PLA replacement from them. The actual chips are GAL20V8B chips, preferably the -25LP but with an alternate programing of the one chip you can use the faster -15LP chips instead. The chips can be programmed by downloading the .jed files from the Daniel’s project website: https://www.freepascal.org/~daniel/c64pla/

2021年1月26日 · Alternative KERNALs can really put the PLA to the test, especially KERNAL cartridges, which change the C64 mode twice per half cycle and thus require a very responsive PLA. This has been tested with the 1541 Ultimate II, …

2016年12月19日 · The most common cause of a black screen on the old Commodore 64 long boards is a broken Programmed Logic Array (PLA) chip located at position U17. Based on different input signals, the PLA creates chip select signals and controls which chip is to be connected to the data bus.

2023年2月21日 · The PLA20V8 is a aftermarket replacement for the C64's failure prone PLA custom chip. The PLA20V8 is designed to be an easy to install low-cost replacement for the original chip. The PLA20V8 consists of two GAL20V8B chips from Lattice Semiconductor mounted on a small PCB.