Debug port pins 13 and 14

[spicemuseum]

Some modchips such as Xecuter X3 use LPC debug pins 13 and 14, others such as Aladdin do not.

Despite looking around I can't find a description of what those pins are and how the e.g. X3 uses them. Anyone know or can provide a link?

[Heimdall]

That's the i2c bus connection. It's used, among other things, to get direct access to the eeprom. If you fit an X3 chip, and it will boot a standard BIOS (X2, Evox M8+, iND-BIOS), but won't boot an X3 BIOS, then you haven't soldered pins 13 and 14 properly.

Code: Select all

Pin	Signal	Pin	Signal
20	A20GATE	19	 RC#
18	SERIRQ	 17	 VSS
16	SPDA0	  15	 SPDA1
14	SDA		 13	 SCL
12	VSS		 11	 LAD0#
10	LAD1#	  9 	 VCC3
8	 LAD2#	  7 	 LAD3#
6	 VCC5		5	  LRST#
4	 KEYWAY	 3	  LFRAME#
2	 VSS		 1	  LCLK

This is a standard LPC pinout. Obviously pins 17-20 aren't presented on the Xbox LPC, which only goes up to 16 pins.

[spicemuseum]

I just confirmed I2C SDA and SCL (EEPROM access) by more persistent googling. Remembered that it's those pins you use when recovering EEPROM data from a bu99ered box.

--edit--
See your post agrees, thanks Aitch.

[fxmech]

Does "among other things" happen to include communication with the LCD?