Talk:EMU

From OpenEZX

UART mode Pinout :

1 NC 2 TXD 3 RXD 4 ??? 5 GND The routing of the analog switches is exactly the same as in USB client mode, but inside the PCAP chip, the USB transceiver is bypassed. TXD is bypassed to GPIO 39 of the AP (which is then TXD of FFUART) and RXD is bypassed to GPIO 53 (which is then RXD of FFUART). See drivers/misc/ezx-emu.c of the original kernel for code.

what's means the "???" of the pin 4?

Well, the ??? of pin4 means that it is as of yet unknown if there is a resistor / voltage that can be applied to pin 4 in order to have the original motorola kernel switch to serial mode. If motorola has an "original serial cable", then we don't currently know what would be connected on its pin 4. We know the pinout of serial mode (usb pin2 -> GPIO 39 (TX of FFUART) & usb pin3 -> GPIO 53 (RX of FFUART) ) by looking at the original kernel source, however, the voltage of pin4 can not be simply derived from code in original motorola kernel, thats why there are "???". Hope this helped. Please feel free to clarify / adapt the Wiki article.