Newbie looking for advice on small glue logic in CPLD/FPGA/...

[softfoot]

Hi, I need to put together a small microprocessor based controller that needs to be as small as possible, 5V based with some fairly complex external logic so I am thinking about a CMOS Programmable Logic Array (or such) that can be repeatably reprogrammed during development. I am probably talking about a 24 or max 32 pin package.

It would need maybe 10 latches and 20 gates.

I have considerable knowledge in electronics but not with these devices and want to gain some experience in using these, but the only thing is I am on a tight budget so free development and programming software is essential.

Advice on programming hardware (cheap) is also needed

Can anyone recommend a manufacturer/devices/programmer that meets this need ??

I am happy with github/sourceforge software or free manufacturers tools.

TIA
Dave

[mikeselectricstuff]

Have you looked at Cypress Psoc to integrate the logic and MCU?
Lattice XO2 may be an option. Note the Lattice CPLDs need software that is no longer free
If you really need 5V in & out, Atmel/Microchip ATV750 or ATV2500 might be worth a look.

[Someone]

You said "external" logic, but as mentioned above you might look at integrating the microcontroller with the logic in one device if that might be smaller in size and more convenient and maybe easier in some ways.

Absolutely, along with the PSOC some of the modern Microchip (Atmel) parts have programmable asynchronous "events" that provide rich interconnect between not just pins and hardware peripherals but also to/from LUTs and registers. Sadly not much in the way of 5V parts there either! Finding the right micro with the perfect matching capabilities is some what of a task, but probably easier than finding 5V programmable logic

[TomS_]

Too much logic for something like a GAL, but should easily fit inside a small CPLD. Unless you were ok with multiple GALs...

5V kind of limits the options. Altera and Xilinx had 5V products, but at least Altera doesn't produce them any more so you are stuck buying them second hand or new old stock if you are lucky enough. The EPM7000 series can be programmed in VHDL or Verilog and start from 32 macrocells in 44 pin packages.

Atmel has a current 5V product line in the ATF150x family of devices which you can still purchase new. They are so similar to the EPM7000 parts that you can translate the design from Altera to Atmel using a free tool. Alternatively you can use WinCUPL to design the logic.