Program Examples For 16-Bit Timer/Counter - Fujitsu F2MC-8L MB89620 Series Hardware Manual

9
9.

Program Examples for 16-bit Timer/Counter

This section gives program examples for the 16-bit timer/counter.
n Program Example for Interval Timer Function
l Processing description
• Generates 25 ms interval timer interrupts.
• The interrupt processing routine resets the TCR register for the next interrupt.
• The following shows the TCR register value that results in an interval time of 25 ms for a
10 MHz source oscillation.
Coding example
l
TMCR
TCHR
TCLR
TCEF
TCS
ILR2
INT_V
IRQ6
INT_V
;-----Main program----------------------------------------------------------------------------------------------------------------------------------------
;-----Interrupt processing routine----------------------------------------------------------------------------------------------------------------------
WARI
;---------------------------------------------------------------------------------------------------------------------------------------------------------------
194
CHAPTER 9 16-BIT TIMER/COUNTER
16
TCR register value = 2
EQU 0018H
EQU 0019H
EQU 001AH
EQU TMCR:2
EQU TMCR:0
EQU 007DH
DSEG ABS
ORG 0FFEEH
DW WARI
ENDS
CSEG
:
CLRI
CLRB TCS
MOV ILR2,#11011111B
MOV TCHR,#0BH
MOV TCLR,#0DCH
MOV TMCR,#00100011B
SETI
:
MOV TMCR,#00100000B
PUSHW A
XCHW A,T
PUSHW A
MOVW A,TCHR
MOVW A,#0BDCH
CLRC
ADDCW A
MOVW TCHR,A
MOV TMCR,#00100011B
:
User processing
:
POPW A
XCHW A,T
POPW A
RETI
ENDS
END
– 25 ms/(4/10 MHz) = 3036 (0BDC
; Address of the 16-bit timer control register
; Upper address of the timer count register
; Lower address of the timer count register
; Define the interrupt request flag bit.
; Define the count start bit.
; Address of the interrupt level setting register 2
; [DATA SEGMENT]
; Set interrupt vector.
; [CODE SEGMENT]
; Stack pointer (SP) etc. are already initialized.
; Disable interrupts.
; Stop counter operation.
; Set interrupt level (level 1).
; Set data for 25 ms timer.
; Store counter value, operate interval timer, clear interrupt
request flag, enable interrupt request output, and start counter
operation.
; Enable interrupts.
; Clear interrupt request flag. Stop counter operation.
; Add time from overflow until interrupt accepted.
; 25 ms timer data (for 10 MHz).
; This does not consider the case when an overflow occurs during
the addition.
; For absolute accuracy, the time while the counter is stopped
should be added.
; Enable interrupts and start the count.
)
H
MB89620 series