TIMER/COUNTER UNIT
9-18
Example 9-1. Configuring a Real-Time Clock
$mod186
name example_80186_family_timer_code
;FUNCTION:
This function sets up the timer and interrupt controller
;
to cause the timer to generate an interrupt every
;
10 milliseconds and to service interrupts to
;
implement a real time clock.
;
;
Timer 2 is used in this example because no input or
;
output signals are required.
;
;SYNTAX:
extern void far set_time(hour, minute, second, T2Compare)
;
;INPUTS:
hour - hour to set time to.
;
minute - minute to set time to.
;
second - second to set time to.
;
T2Compare - T2CMPA value (see note below)
;
;OUTPUTS:
None
;NOTE:
Parameters are passed on the stack as required by
;
high-level languages
;
;
For a CLKOUT of 16Mhz,
;
;
f(timer2)
= 16Mhz/4
;
= 4Mhz
;
= 0.25us for T2CMPA = 1
;
;
T2CMPA(10ms)
= 10ms/0.25us
;
=
10e-3/0.25e-6
;
= 40000
;substitute register offsets
T2CON
equ xxxxh
;Timer 2 Control register
T2CMPA equ xxxxh
;Timer 2 Compare register
T2CNT
equ xxxxh
;Timer 2 Counter register
TCUCON equ xxxxh
;Int. Control register
EOI
equ xxxxh
;End Of Interrupt register
INTSTS equ xxxxh
;Interrupt Status register
timer_2_int
equ 19
;timer 2:vector type 19
data segment public ’data’
public _hour, _minute, _second, _msec
_hour db ?
_minute db ?
_second db ?
_msec db ?
data ends
Содержание 80C186XL
Страница 1: ...80C186XL 80C188XL Microprocessor User s Manual...
Страница 2: ...80C186XL 80C188XL Microprocessor User s Manual 1995...
Страница 18: ...1 Introduction...
Страница 19: ......
Страница 27: ......
Страница 28: ...2 Overview of the 80C186 Family Architecture...
Страница 29: ......
Страница 79: ......
Страница 80: ...3 Bus Interface Unit...
Страница 81: ......
Страница 127: ......
Страница 128: ...4 Peripheral Control Block...
Страница 129: ......
Страница 137: ......
Страница 138: ...5 ClockGenerationand Power Management...
Страница 139: ......
Страница 154: ...6 Chip Select Unit...
Страница 155: ......
Страница 178: ...7 Refresh Control Unit...
Страница 179: ......
Страница 193: ......
Страница 194: ...8 Interrupt Control Unit...
Страница 195: ......
Страница 227: ......
Страница 228: ...9 Timer Counter Unit...
Страница 229: ......
Страница 253: ......
Страница 254: ...10 Direct Memory Access Unit...
Страница 255: ......
Страница 283: ......
Страница 284: ...11 Math Coprocessing...
Страница 285: ......
Страница 302: ...12 ONCE Mode...
Страница 303: ......
Страница 306: ...A 80C186 Instruction Set Additions and Extensions...
Страница 307: ......
Страница 318: ...B Input Synchronization...
Страница 319: ......
Страница 322: ...C Instruction Set Descriptions...
Страница 323: ......
Страница 371: ......
Страница 372: ...D Instruction Set Opcodes and Clock Cycles...
Страница 373: ......
Страница 396: ...Index...
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