XO1.5 ECIRQ ECO
This describes a change to early prototypes of the XO-1.5 motherboard. It simplifies the EC interrupt handler used in communicating with the EC, by duplicating the EC interrupt on another interrupt input which isn't "owned" by ACPI.
This only applies to XO-1.5 B2 phase motherboards.
Ask Paul Fox (pgf at laptop.org) for more information.
Note that you must first have performed the alternate version of the DCON Interrupt ECO.
- Cut the short thin horizontal trace between R123 and a nearby via (leave the long vertical trace between R123 and a distant via intact). R123 is located on the "top" side of the motherboard, opposite of the processor and most chips. It is between the backside of the VX855 and the LCD connector.
- Wire the pad of R123 connected to a thin trace to the pad of R121 connected to a thin trace. R121 is located slightly below R123, on the top side of the motherboard.