I'm finding it hard to understand. What is the difference between PLA and ROM? Can somebody please provide a link or explanation?
Electronic – the difference between PLA and ROM
digital-logicprogrammable-logicrom;
Related Solutions
In a retriggerable MMV a new trigger during a pulse will restart the pulse time, and thus extend the current pulse.
If the pulse time is 10 s and you would retrigger 6 s after the first trigger you would get a 16 s pulse.
In a non-retriggerable MMV the second trigger will be ignored and you'll get a 10 s pulse:
The circuit is an adder with \$F[2:0]=A[1:0]+B[1:0]\$.
Best Answer
They are quite different devices.
PLA = Programmable Logic Array.
A PLA or PAL (programmable array logic) device is like a baby FPGA which can be programmed to perform basic logic functions. Tens to hundreds of gates on a PAL can be connected to perform simple logic functions. A PAL is often read only, in that after programming you have to perform a complete erase to update it.
ROM = Read Only Memory.
A ROM does not perform logic functions, but stores data. A type of ROM might be EPROM, eraseable programmable read only memory.
You can use a ROM as a logic device, by implementing a simple logic table lookup. Like a truth table. However, it is somewhat wasteful and expensive to do this compared to actually using a PAL or even a CPLD/FPGA.