CH559 Port 4 "OC" mode

[Tonymac32]

ch55xduino/ch55xduino/ch55x/cores/ch55xduino/wiring_digital.c

Line 165 in 333ef3e

//todo: OC mode for CH559

I have configured the pins on Port 4 as output to use I2C devices with them. Port 4 has a drive limit:

bP4_DRV - P4 port output drive capability selection, this bit is 0 to select the drive current 5mA level. This bit is 1 to select the drive current 20mA level

At default 0 this seems safe for the attached devices. It might be a usable workaround.