|0: Normal entry|
|R1||Colour (&BBGGRRSS format)|
|R4||Bits 0-23: 12 (reason code)|
|Bits 24-31: Driver number|
|R1||Updated colour (&BBGGRRSS format)|
|-||All other registers preserved|
The kernel issues this call to obtain the effective colour of a palette entry after taking into account any hardware restrictions in the video controller. The appropriate driver should respond by updating the colour value in R1 (if necessary) and setting R4 to 0 to claim the call.