It should be fairly straightforward to write and read a 25xxx eeprom thru the SPI bus using the pc serial port with Keil software. But nowhere do I find the DB-9 to SPI connections. Which pins connects to sck, mosi, miso,cs ? Can you help? Thanks, John
'Finally, "FWIW, I happen to have used TD<->SCK, DTR<->MOSI, and CTS<->MISO through RS-232 transceivers for some bit-banged applications. " Isnt this going to depend on the software ?' Yes, my software is structured so that one can pretty much move RS-232 to SPI signal assignments around to suit their needs (assuming one does not violate the "directions" of the RS-232 signals). In my case, the client wanted to use a standard DB-9 serial cable from PC to target to both communicate normally between PC and target application, and perform in-system target MCU (re)programming using SPI without any other special external hardware.