You can set the GPIO numbers for the PS/2 interface in the registry.

[HKEY_LOCAL_MACHINE\HARDWARE\DEVICEMAP\Mouse]
"clockGPIO"=dword:0e   ;Set the GPIO number. If you set the value to ffffffff (-1) no GPIO is used
"dataGPIO"=dword:13    ;Set the GPIO number. If you set the value to ffffffff (-1) no GPIO is used

Colibri Tegra

By default on the Colibri Tegra PS2 is disabled. The first image supporting PS2 is image V1.1beta2. To enable it you need to add the registry keys.

If you like to use the standard pins on the Colibri T20 you need to add:

[HKEY_LOCAL_MACHINE\HARDWARE\DEVICEMAP\Mouse]
"clockGPIO"=dword:0f   ;decimal 15, GPIO B_7, SODIMM 63
"dataGPIO"=dword:0e    ;decimal 14, GPIO B_6, SODIMM 55

In image V1.1beta2 you need to deactivate DFS to use the PS2.

Colibri Vybrid

By default on the Colibri Vybird PS2 is disabled. To enable it you need to add the registry keys.

If you like to use the standard pins on the Colibri Vybrid you need to add:

[HKEY_LOCAL_MACHINE\HARDWARE\DEVICEMAP\MOUSE]
"clockGPIO"=dword:26 
"dataGPIO"=dword:27 
"Priority256"=dword:91