IBM AT 5170 Technical Reference page 427

SECTION 9. IBM PERSONAL
COMPUTER COMPATIBILITY
Contents
Hardware Considerations •...•......•......•.....•... 9-3
System Board ................................. 9-3
Fixed Disk Drive ............................... 9-5
Diskette Drive Compatibility . . . . . . . . . . . . . . . . . . . . .. 9-5
Copy Protection ............................... 9-5
Bypassing BIOS ............................. 9-6
Diskette Drive Controls ....................... 9-6
Write Current Control ........................ 9-6
Application Guidelines .............•................ 9-7
High-Level Language Considerations ............... 9-7
Assembler Language Programming Considerations .. . .. 9-8
Multitasking Provisions ......................... 9-16
Interfaces ................................. 9-16
Classes ................................... 9-17
Time-Outs ................................ 9-19
Machine-Sensitive Code ........................ 9-19
Compatibility 9-1