Electrical Engineering Stack Exchange
Electrical Engineering Stack Exchange

Questions tagged [programmable-logic]

Programmable digital logic devices include FPGAs, CPLDs, and older devices such as GALs and PALs. Programmable logic enables flexibly implementing complex digital functions in a single chip, from a few gates of glue logic to entire microprocessors or complex signal processing systems.

Typically FPGAs and CPLDs are programmed using VHDL or Verilog.

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Is there an inexpensive way to get started with GAL (Generic Array Logic) chips?

GAL chips seem expensive to get started with, since programmers cost hundreds of dollars and even ISP cables aren't cheap. Is there a cheaper way?
samoz
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What are my less expensive options for getting started with CPLDs

I would like to goof around with some CPLD stuff and I see I have a couple options out there. I don't have a particular application in mind; it just seems like there a lot of possibilities, some of which are easier to use than others. The main…
mmccoo
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What is the difference between a GAL and a PAL?

I was reading this article (unfortunately a lengthy Dutch discussion) talking about a GAL. I have come across the GAL device before, but never really understood what a Generic Array Logic is. I know what a PAL is and I am under the impression that…
jippie
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Export restrictions on programming equipment

I have a friend that works for an overseas manufacturer. He sells programming equipment to companies that have products with multiple Programmable Controllers embedded. I raised the subject of "export Control" requiring a special export license, and…
Larry
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Any programmable devices available for more modern languages?

Pardon my naïveté, but it seems like most programmable devices (FPGAs, PLCs, PICs, etc.) are programmable using the C or C++ languages, or a variant of one of these. Are there any devices out there that use something like D, Mozilla Rust, or Google…
arussell84
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Can a CPLD be reprogrammed just like a Microcontroller?

Given that microcontrollers can be reprogrammed multiple times, does this apply to CPLDs as well? In particular, I am interested in Xilinx's CoolRunner-II. Until now, I was positive about the re-programability, but after looking at the specs at one…
Nazar
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Please explain this price difference

When I paid a visit to my component supplier I spotted a few GAL22V10 available there. Asked the price - CNY24 (about US$4) a pop, NOS. Then I asked about EPM240T100C5, an 100-pin 240-LU CPLD and the price? CNY6 (about US$1) each, brand new. Even…
Maxthon Chan
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What was the protocol for programming GAL devices?

What actually has to happen, at a pins and signals level, to program a GAL device? Let's say I have a GAL 22V10, and a .JED file with the desired fuse pattern. The usual way to proceed is to drop the chip into a commercial programmer, load the .JED…
JustJeff
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Naming of PLA and PAL

I am studying the Programmable Logic Array (PLA) and Programmable Array Logic (PAL). I understood every detail I found about them including the implementation and difference between them. But I have a very simple question about their naming. Why did…
Osama El-Ghonimy
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Orientation of switching elements in PLA

In a PLA, the switching elements in the wired-OR array are oriented as shown on the right of the figure (from Fundamentals of Logic Design, Roth/Kinney, 6th Ed, p.264). A logic 1 current appears to flow in the direction of the arrows, from word line…
int
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How to wire the output of a PLC

I have question regarding the wiring of the output of PLC (mode: Omron CP1L). Below is the output wiring diagram. The PLC is AC powered, and input are 24 VDC. As the image shows, the output has a "+" and a "-" that supply a DC voltage. 00-07 are…
KMC
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IO voltage properties in CPLD

I am using CoolRunnerII CPLD and wish to know what is the I/O Voltage Standard setting in the fitting properties: I know that Vcc must be 1.8V. I also know that I define the IO bank voltage by providing externally voltages to Vccio1 and Vccio2. So,…
Nazar
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Any nice way to use unbonded CPLD pins as registers

Many CPLD product families offer each chip in multiple packages, some of which don't bond all I/O pads out to pins. Even I/O pads which aren't bonded to pins, however, may be useful if they have bus-keeper circuits. Enable the bus keeper on a pin…
supercat
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What is the algorithm to read fusemap from PAL IC?

I am aware that it's not always possible due to security fuse, but I would like to at least try to read the fusemap from a certain PAL16R6 chip. I would like to do it using MCU like Arduino, not a dedicated expensive programmer. Problem is, that I…
woytekm
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Programmable Logic Controller

I have 4 DC powered electro magnets which I am currently running at 16 Volts @ 5 amps using a variable DC power supply. I want to build a programmable controller that would allow me to control the following functions: Polarity for each magnet…
David Burnham
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