IBM RT Series Hardware Reference Manual page 334

TNL SN20-9844 (March 1987) to 75X0235
I/O Mapped Register Addressing
The Extended Monochrome Graphics Display Adapter responds to I/O addresses ranging from
X'ODI0' to X'OD2F' and X'06F3'.
I/O Address Access Function Performed
H'06F3' Write Interrupt Level 11 Acknowledge
H'ODI0'
Write Write Mode Register
X'ODI2'
Write Write Control Register
X'ODI4'
Write Increment Queue Counter
X'ODI6'
Write Diagnostic Promlevel Check
X'ODI8' Write Reserved
X'ODIA' Write Enable Video Data Output
X'ODIC' Write
Reserved
X'ODIE'
Write Reserved
X'OD20' Write Reset Adapter
X'OD22'
Write Reset Frame Sync Interrupt
X'OD24' Write Reset Raster Operation Interrupt
X'OD26' Write
Disable DMA Processing
X'OD28'
Write
Enable DMA Processing
X'06F3' Read Reserved
X'ODI0' Read Reserved
X'ODI2'
Read Read Status Register
X'ODI4'
Read Reserved
X'ODI6'
Read Reserved
X'ODI8'
Read Reserved
Figure 15 (Part 1 of 2). I/O Address Function Table
22 Extended Monochrome Graphics Adapter