Hello FreeCalypso community, I finally got a breakthrough in the wild goose chase after the sleep mode hardware bug on our FCDEV3B boards: the self-reboot behaviour on the AT+CFUN=1 command with all sleep modes enabled went away when I replaced the high-capacity flash+RAM chip on one experimental board with the smaller-capacity K5A3281 that was used by Openmoko. Thus we now know that the difference between Openmoko's working original and our derivative thereof that's causing the sleep mode bug is the memory IC change.
My next goal is to figure out how to fix the erratic behaviour without reducing the memory capacity, i.e., how to make sleep modes work correctly without giving up the high-capacity Spansion flash+pSRAM chip we are currently using. The inspiration to use this particular chip (Spansion S71PL129NC0HFW4B) came from the Pirelli DP-L10, and the part number was obtained by reading the marking on the flash+RAM chip inside a disassembled Pirelli DP-L10 phone. These chips clearly work fine in these phones, and all sleep modes work fine when we run our own fw on the Pirelli target, thus it is clearly possible to use this memory chip in a Calypso phone or modem. My next experiment will be to try increasing the bypass capacitor values on the V-FLASH and V-SRAM power supply nets from the Iota ABB to the memory chip - stay tuned. Hasta la Victoria, Siempre, Mychaela aka The Mother _______________________________________________ Community mailing list Community@freecalypso.org https://www.freecalypso.org/mailman/listinfo/community