I have an interest in Daryl's 65SPI, and I'm trying to understand the WinCUPL source code. I know it uses the PLCC ATF1504, but I have a couple of breadboard-friendly DIP ATF2500 on hand. It has fewer macrocells, however, could I use it instead? How can I know, by looking at the WinCUPL file, how many macrocells are required?

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Fred Segard
A.K.A. The Micro Hobbyist
https://6502sbc.blogspot.com/

I don't think you can tell just by looking at the CUPL. It depends on the capabilities of your device's macrocells, inter-cell routing etc etc. If you run the fitter for the CUPL for your device, it will tell you how many Macrocells it uses and/or whether or not it fits.

That being said, from memory, I believe that the 65SPIv2 only just fits in an ATF1504 so if your ATF2500 has fewer macrocells I would suggest the 65SPIv2 is unlikely to fit.

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Also, I maintain KiCad libraries of Retro Computing and Arduino components you might find useful.

I ported 65SPI to Altera Quartus schematic for EPM7064S which is very similar to ATF1504 with 64 macrocells. The full design uses 53 macrocell, but significant amount of macrocells are for SlaveSelect (8), option registers (6) and multiplexing of data from various registers. So if you only want to control a couple devices and don't want the various programmable features, the core design can be reduced below 40 macrocells. It may fit an ATF2500.
Bill

viewtopic.php?f=4&t=1265&p=85825&hilit=65spi#p81452
https://www.retrobrewcomputers.org/doku ... 5spi_proto

I made a variation for the Xilinx 9572, I believe it would also work with the 5V tolerant 9572xl (as pure 5V devices have been discontinued)
http://www.6502.org/users/andre/spi65b/

OTOH those are PLCC as well...

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Author of the GeckOS multitasking operating system, the usb65 stack, designer of the Micro-PET and many more 6502 content: http://6502.org/users/andre/

Do you have a way to program the ATF2500s? Last time I checked it was only supported in old, obsolete programmers.

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x86?  We ain't got no x86.  We don't NEED no stinking x86!

In addition to resource limits, the registers need to support asynchronous set and reset. The ATF2500 uses a synchronous Set. I have not explored the modifications needed to enable the use of synchronous signals in the 65SPI logic, so it may be possible to modify the code to allow it. However, I do not indent to explore that myself.

thanks!

Daryl

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Urghh! You're right! My programmer does not support the ATF2500. Darn! That solves that issue.

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Fred Segard
A.K.A. The Micro Hobbyist
https://6502sbc.blogspot.com/

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x86?  We ain't got no x86.  We don't NEED no stinking x86!