IBM 5150 PC Technical Reference (6025005, August, 1981) (PDF)

Programming Considerations
Asynchronous Communications Adapter (continued)
Modem Status Register 2-143
Receiver Buffer Register 2-144
Transmitter Holding Register 2-145
Color/Graphics Monitor Adapter
Color Select Register 2-57
Control and Status Register 2-57
I/O Address and Bit Map 2-61
Interrupt Level 2-60
Mode Register Summary 2-58
Mode Select Register 2-58
Programming the 6845 Controller 2-55
Programming the Modem Control and Status Register 2-57
6845 Register Descriptions 2-56
Status Register 2-59
Sequence of Events 2-59
5 1/4" Diskette Drive Adapter
Command Status Registers 2-100
Command Summary 2-96
Symbol Descriptions 2-94
IBM Monochrome Display and Parallel Printer Adapter
DMA Channel 2-42
I/O Address and Bit Map 2-42
Interrupt Levels 2-42
Memory Requirements 2-41
Sequence of Events 2-41
Programming the CRT Controller 2-41
Programming the 6845 CRT Controller 2-41
Comments 2-104
DPC Registers 2-103
Drive Constants 2-104
R
RAS 2-114
Rating Amps, Over Voltage/Current Protection 2-36
Ready Line 2-8
Read Block 3-9
Read Data 2-107,2-108 (5 1/4" Diskette Drives, External) 2-109
Read Status (Parallel Printer Adapter Block Diagram) 2-66
Read/Write Memory
Color Monitor 2-50
Color TV 2-49
Future Expansion in I/O Channel, 384 KB 2-26
1-15