KS152JB Universal Communications Controller
Technical Specifications
Kawasaki LSI USA, Inc. Page 15 of 120 Ver. 0.9 KS152JB2
Mode 3 is used in cases where an extra 8 bit timer is needed. With Timer 0 in Mode 3, Timer 1 can
be turned on and off by switching it out of and into its own Mode 3. It can also be used as a baud
rate generator for the serial port.

2.8 Interrupts

The cpu has a provision for 11 different interrupt sources. These are the two external interrupts,
the three timer interrupts, the local serial port interrupt, dma interrupt and global serial port inter-
rupts.
The External Interrupts INT0 and INT1 can be either edge triggered or level triggered, depending
on bits IT0 and IT1. The bits IE0 and IE1 in the TCON register are the flags which are checked to
generate the interrupt. When an interrupt is generated by these external interrupt inputs, they will
be cleared on entering the Interrupt Service routine, only if the interrupt type is edge triggered. In
S3P1OSC I0
I1 Q
GATE
INT0
pin
TR0
T0 pin
TL0
5 bits TF0 INTERRUPT
C/T
Timer/Counter 0 in Mode 3
TH0
8 bits TF1 INTERRUPT
S3P1
TR1
EA -- -- ES ET1 EX1 ET0 EX0
76543210
EA Global Disable bit. If this bit is cleared it disables all the interrupts at once.
IE: Interrupt Enable Register.
If EA is 1 then interrupts can be individually enabled/disabled by setting or
clearing its own enable bit.
reserved.--
EX0
ET0
EX1
ET1
ES
External interrupt 0 enable
Timer 0 interrupt enable.
External interrupt 1 enable.
Timer 1 interrupt enable.
Local Serial port interrupt enable.