Section 1. System Board - IBM AT 5170 Technical Reference

SECTION 1. SYSTEM BOARD
Contents
Memory .................•...•............•.•..•• 1-4
Microprocessor ................•.................. 1-4
Real Address Mode .......................... 1-4'
Protected (Virtual Address) Mode .............. 1-5
System Performance ..•............•••.•....••..... 1-7
DirectMemory Access .................•...•..•...• 1-9
System Interrupts ................................ 1-12
Hardware Interrupt Listing ...................... 1-13
Interrupt Sharing .............................. 1-14
Design Overview ........................... 1-14
Program Support ........................... 1-15
Precautions ............................... 1-17
Examples ................................. 1-18
System Tinters .........•.........•.........••...• 1-22
System Clock .......................••........... 1-23
ROM Subsystem 1-23
RAM Subsystem
1-24
110 Channel .................................... 1-24
Connectors .................................. 1-25
110 Channel Signal Description .................. 1-31
NMI and Coprocessor Controls .................. 1-38
Other Circuits .............•.•...........•...••.. 1-40
Speaker ..................................... 1-40
RAM Jumpers ................................ 1-40
System Board 1-1