Apr 19th Update
- - not started yet //cmxp going to start looking at 65SPI and SDCard circuit next
- Started working on this a week or so ago
- To start with I repurposed a 4×6 perf board that already had a XC9572XL on it that I did my original devsel testing on. That’s it’s main function along with inverting the apple2 read/write signal for the sn74LVCCC4245A OCTAL DUAL-SUPPLY BUS TRANSCEIVER
- The SPI logic is a copy of the code from Daryl Rictors 65SPI project. My thanks go out to Daryl for sharing this code with the community and patiently answering all my questions about it.
- The code is running in a EZ-DIGITAL XC95144XL-TQ100 breakout board I purchased from Justin.
- Murphys law came into effect when I inadvertently set an inversion flag on one of the Logic Analyzer probes which was attached to the MISO line. This stumped me for awhile.
- Next up is to write some software to make a loadable disk driver for ProDOS so I can test things out in general. I want to see if the SPI controller runs into the same glitch on the IIc+ as my sram interface did.
- Currently wired is a standard SDCard conenctor. I also have a MicroSD card connector wired up for the second SPI device. The third SPI device will be a wifi-card it is surface mountable so I need to make a mini break out for it.
- The compact flash interface is mounted but needs to be wire wrapped to the remaining available pins on the CPLD.
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