Filter
Top Products
125
CHAPTER 5 TIME-BASE TIMER
5.7 Program Example for Time-base Timer
Programming examples for the time-base timer are shown below.
■ Programming Examples for Time-base Timer
● Processing specification
Repeatedly generate an interval timer interrupt at intervals of 2
18
/F
CH
(F
CH
: oscillation frequency). The
time interval is approximately 21.0 ms (operating at 12.5 MHz).
● Coding examples
TBTC EQU 0000AH ; Address of time-base timer control register
TBOF EQU TBTC:7 ; Definition of interrupt request flag bit
ILR2 EQU 007CH ; Address of interrupt level setting register 2
INT_V DSEG ABS ; [DATA SEGMENT]
ORG 0FFECH
IRQ7 DW WARI ; Setting interrupt vector
INT_V ENDS
;------------------------Main program---------------------------------------------------------------------------------
CSEG ; [CODE SEGMENT]
; Stack pointer (SP) or other registers are assumed to
have been initialized.
:
CLRI ; Interrupt disable
MOV ILR2,#01111111B ; Setting interrupt level (level 1)
MOV TBTC,#01000100B ; Clearing interrupt request flag, enabling interrupt
request output, selecting 2
18
/F
CH
, and clearing
time-base timer
SETI ; Interrupt enable
:
;------------------------Interrupt processing routine------------------------------------------------------------------
WARI CLRB TBOF ; Clearing interrupt request flag
PUSHW A
XCHW A,T
PUSHW A
:
User processing:
:
POPW A
XCHW A, T