Service manual

36
8575
8575
A N/B Maintenance
A N/B Maintenance
1.2.9 Keyboard System: H8 (3437S) Universal Keyboard Controller
CPU Two-way general register configuration
Eight 16-bit registers or sixteen 8-bit registers
High-speed operation
Maximum clock rate: 16Mhz at 5V
Available in temperature range: 0°C~70°C
Memory Include 60KB ROM and 2KB RAM
16-bit free-running timer
One 16-bit free-running counter
Two output-compare lines
Four input capture lines
8-bit timer (2 channels) Each channel has one 8-bit up counter, two time constant registers
PWM timer (2 channels) Resolution: 1/250
Duty cycle can be set from 0 to 100%
I
2
C bus interface (one channel) Include single master mode and slave mode
Host interface (HIF) 8-bit host interface port
Three hosts interrupt requests (HIRQ1, 11,12)
Regular and fast A20 gate output
Keyboard controller Controls a matrix-scan keyboard by providing a keyboard
scan function with wake-up Interrupts and sense ports
A/D converter 10-bit resolution
8 channels: single or scan mode (selectable)