Honored Contributor
Honored ContributorOkay, here's what I see on the EPCS1 when I reconfigure my Cyclone EP1C3:
nCS falls Send 0x05, receive 0xFF: Read status register command Send 0xFF, receive 0x00: SR is 0. nCS rises, then falls after 450 ns. Send 0xAB, receive 0xFF: Release from Power Down and read signature Send 0x00, receive 0xFF: dummy byte# 1 Send 0x00, receive 0xFF: dummy byte# 2 Send 0x00, receive 0xFF: dummy byte# 3 Send 0x00, receive 0x10: Signature is 0x10 (EPCS1) (I saw 9 bits clocks, not 8, for this byte) nCS rises, then falls after 2.2 us. Send 0x03, receive 0xFF: Read array continuous Send 0x00, receive 0xFF: address byte# 1 Send 0x00, receive 0xFF: address byte# 2 Send 0x00, receive 0xFF: address byte# 3 After this, it kept nCS low while reading the data bytes. So much for hijacking AS mode. I can still do what I was planning on in the first place, but maybe I'll need to have the AVR control the MSEL0 pin so I can switch it between AS mode and PS mode, using PS mode during configuration and AS mode during runtime (so the ASDO and nCSO pins on the Altera work for the flash programmer). I'm amused it checks the signature byte.
