How to test memory in an HP48 RAM card

[mfleming]

(01-24-2021 07:04 PM)Jonathan Busby Wrote:  If the Cypress F-RAM chip had a, say, 192MHz clock instead of just 40MHz, then there'd be no problem. I've been in correspondence with a Cypress Semiconductor engineer, so we might find out if Cypress Semi is planning on releasing faster chips any time soon.

I've looked at a number of persistent memories and the fastest clock I can remember seeing was 66 MHz. See what's available in quad-SPI memory. With a higher clock rate that might get you in range, though I know of no low end microcontroller with hardware QSPI support.