HT48RA0-5 Holtek Semiconductor, HT48RA0-5 Datasheet - Page 12

• Manufacturer Part Number: HT48RA0-5
• Description: Remote Type 8-Bit OTP MCU
• Manufacturer: Holtek Semiconductor

Timer
The timer is an internal unit for creating a remote control
transmission pattern. As shown, it consists of a 9-bit
down counter (t8 to t0), a flag (t9) permitting the 1-bit
timer output, and a zero detector.
Rev.1.00
0~7
2~6
No.
No.
0
1
7
Label
Label
TOEF
t0~t7
t8
t9
TSR0 (18H) Register
TSR1 (19H) Register
Down counter
Down counter
Timer enable, initial value is 0 .
Unused bit, read as 0 .
Timer operation end flag, initial
value is 1 .
Function
Function
PA and PB Input/Output Ports
REMDRV output pin structure
PC0 Input/Output Port
12
Timer Operation
The timer starts counting down when a value other than
instruction. The timer manipulation instructions for mak-
ing the timer start operation are shown below:
MOV A,XXH
MOV TSR0,A
MOV A,XXH
MOV TSR1,A
SET TSR1.1
Addition notes for the 9-bit timer:
0 is set for the down counter with a timer manipulation
Writing to TSR0 will only put the written data to the
TSR0 register (t7~t0) and writing to TSR1 (t8) will
transfer the specified data and contents of TSR0 to
the Down Counter. TOEF will be cleared after the data
transferred from TSR1 and TSR0 to the Down Coun-
ter is completed and then wait until TSR1.1 is set by
user.
Setting TSR1.1=1, the timer will start counting. The
timer will stop when its count is equal to 0 and then
TOEF is set equal to 1 .
; XX = 00H ~ FFH
; XX
; The timer is started by set t9=1
01H, t8
HT48RA0-5
March 23, 2010
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