PPC-IOP UART
The PPC-IOP UART RX and TX are accessible through an unpopulated connector footprint located on the B side (underside) of the motherboard (together with the EE UART and some other signals). This connector footprint seems to be consistent across all 75K and later models. The PPC-IOP UART signals use 3.5V logic levels and the baud rate is 57600 bps. When powered on or reset the following message is sent:
D E C K A R D compiled $date
UART location on SCPH-75xxx
(GH-040-??
):
Photo credit: Nox
UART location on SCPH-75xxx
(GH-037-12
):
Photo credit: El Isra
Using the UART from an application
The PowerPC UART TX/RX registers are accessible from both EE and IOP.
The TX reg corresponds to the address 0x1F80380C
On latest PS2SDK, you already have available an IRX module that will redirect stdout to the UART. it is located on $PS2SDK/iop/irx/ppctty.irx