Appendix B
Specifications
Main Unit
16-bit CPU
Main memory
Coprocessor
Read Only Memory
(ROM)
Direct Memory
Access (DMA)
Interrupt (8259)
Timer/counter
(8253-S)
Clock/calendar/RAM
Parallel interface
Serial interface
8088-1 microprocessor; 4.77 or
10 MHz clockrate; switch selectable
640KB
8087-1, 10 MHz microprocessor
(optional)
16KB (ROM BIOS)
Programmable DMA controller with
four channels-two on the
motherboard (one for refreshing and
one for diskette controller), two
available for user peripherals
including a hard disk controller
Programmable interrupt controllers,
8 interrupt levels
Three programmable timer/counters
Real-time clock, calendar, and
SO-byte
CMOS RAM for
configuration, battery back-up
Standard 8-bit parallel, DB-25
female connector; programmable
RS-232C, asynchronous, DB-25
male connector; programmable
Specifications B-1