Specifications

Contents
Interrupt Nesting ............................................ 8-22
Level- or Edge-Triggered
.................................... 8-25
Finish Interrupts
............................................. 8-26
Automatic Priority Rotation
.................................. 8-28
Specific Priority Rotation
.................................... 8-29
Interrupt Masking
........................................... 8-30
Interrupt Status
.............................................. 8-31
Programming
............................................... 8-31
Chapter 9. DMA CONTROLLER (V40) 9-1
OVERVIEW
..................................................... 9-2
ZT 8832 SPECIFICS
............................................. 9-3
FUNCTIONAL DESCRIPTION
................................... 9-4
Internal Bus Interface
......................................... 9-5
Address Register
............................................. 9-5
Address Adjuster
............................................. 9-5
Count Register
............................................... 9-6
Count Adjuster
............................................... 9-6
Control Registers
............................................. 9-6
PROGRAMMABLE REGISTERS
................................. 9-7
DMA Initialize Command (DICM)
............................. 9-8
DMA Channel (DCH)
........................................ 9-8
DMA Base Count/Current Count (DBC/DCC)
.................. 9-10
DMA Base Address/Current Address (DBA/DCA)
.............. 9-11
DMA Device Control (DDC)
................................. 9-12
DMA Mode (DMD)
......................................... 9-13
DMA Status (DST)
.......................................... 9-15
DMA Mask (DMK)
......................................... 9-16
OPERATION
................................................... 9-17
Reset
...................................................... 9-17
Autoinitialization
............................................ 9-18
Programming
............................................... 9-18
Chapter 10. SERIAL COMMUNICATIONS (V40) 10-1
OVERVIEW
.................................................... 10-2
ZT 8832 SPECIFICS
............................................ 10-2
FUNCTIONAL DESCRIPTION
.................................. 10-3
Read/Write Control
.......................................... 10-4
Receiver
................................................... 10-4
Transmitter
................................................. 10-4
Interrupt Generation Logic
................................... 10-4