Specifications

Theory of Operation
OVERVIEW
This chapter describes the following system level issues:
• Processor performance compared to the IBM PC/XT
• STD bus compatibility
• Serial communications using RS-232-C or RS-422/485
• Expanding the ZT 8809A interrupt structure
• Direct Memory Access (DMA) support and benefits
• Methods of battery backup with DC and AC power-fail
detection
• Battery life
• Status indicator access (LED)
• CMOS versions available for extended temperature and low
power
• Processor reset
3-2