SN8P26L38
8-Bit Micro-Controller
SONiX TECHNOLOGY CO., LTD
Page 110
Version 1.5
10
IR OUTPUT
10.1
OVERVIEW
IR signal is generated by IR timer. The IR output pin is IROUT pin
. When IREN bit of IRM is set as logic “1”, IROUT pin
exchanges from GPIO to IR output mode. If CREN = 0 or system is in power down mode, IROUT pin is tied to low
status. The IR timer is an 8-bit binary up counting timer for IR signal generator. The IR signal is duty/cycle changeable
type controlled by IRR and IRD. IRR decides IR’s cycle and IRD decides IR’s duty. IR counter clock source is only from
Fhosc (system high clock source), eg. IHRC_8M, 4MHz or 455KHz crystal. If Fhosc is 4MHz, the IR counter clock rate
is 4MHz. IR timer only generate IR output and no interrupt function. When enable IR output function (CREN=1), IR
output status is low level. IRC initial value is IRR and starts to count. When IRC=IRD, IR output status change to low
level and finishes high duty operation. When IRC overflow occurs (IRC changes from 0xFF to 0x00), IR output low duty
operation stops. System loads IRR into IRC automatically and next cycle starts.
Fhosc
CREN
CPUM0
IRC
8-Bit Binary Up
Counting Counter
IRR Reload
Data Buffer
Up Counting
Reload Value
Compare
R
S
Output Low
IROUT pin
IR Signal
IREN
Load
IRD
Data Buffer
IRC Overflow