# Atmel and Altera CPLD Compatibility Notes

## Overview & Part Numbers

There was a question about it if would be possible to use Altera CPLDs in the S100Computers.com CLPD 386 board, instead of the as-designed Atmel CPLD.

Note that the orginal part specificed is ATF1508AS-10JU84, which is a part with 128 macrocells, and a 10ns t(pd) (125 mhz max) in an 84pin PLCC package.

The corresponding Altera part would be an EPM7128SLC84-10N. Here are the relevant pin diagrams from the two datasheets:

The only major difference between the two appears to be that the ATF1508 part has as GCKL3 pin, which is not present on the MAX7000S part. Otherwise based on the overall datasheets, the parts appear to be pin-compatible.

The implementation provided by John M. is written in WinCUPL for the ATF1508. To use an alternate Altera part, a VHDL or Verilog implementation of the logic equations would be required and would need to be written and tested by the board builder.

## Hardware Cost Comparison

Note - if comparing the cost of *new* hardware for these two systems from a major US supplier like Digiket, the Atmel hardware is less expensive than the Altera hardware.

Altera MAX 7000S CPLDs may be purchased from UTSource.com in China. There are many $10 Altera USB Blaster clones on eBay, but they may not be 100% reliable. Buying an eBay programmer and chips from UTsource brings the cost down to less than the cost of the Altera parts, but possibly at the cost of reliability of the setup. Atmel ATF1508 @ Digikey Altera MAX7000S @ Digikey Altera MAX7000S @ eBay/UTSource Digikey ATDH1150USB-ND Programmer -$60 |[[http://www.digikey.com/product-detail/en/PL-USB2-BLASTER/544-3170-ND/5638362|Digikey USB Blaster II Programmer]] - $225 eBay Chinese clone$7-$17 Digikey ATF1508AS-10JU84-ND CPLD -$13.52 |[[http://www.digikey.com/product-search/en?mpart=EPM7128SLC84-10N&vendor=544|Digikey EPM7128SLC84-10N CPLD]] - $35 UTSource EPM7128SLC84-10N CPLD -$7.50
Total - $73.52 start-up,$13.50/chip recurring Total - $260 startup,$35/chip recurring Total - $14.50-$25.40, \$7.50/chip recurring

## Development Software Comparison

The development software packages for these two options vary:

• Atmel “Free” (as in beer) Development Software
• WinCUPL (used by John M. to create the reference implementation) uses the CUPL hardware definition langauge (Free permanent license)
• ProChip Designer 5.0 uses the VHDL and Verilog HDLs (Two-year license requires approval by Atmel)
• Altera “Free” (as in beer) Development Software