SM59R Timer2 功能使用方法
Application Note
Timer 2 功能使用方法
1
适用产品：SM59R16A2 / SM59R08A2
2
Timer 2 使用概述：
2.1 不仅是一个 16-bit timer，更拥有四信道的比较模式(compare)、捕捉模式(capture)及重载
模式(reload functions). 类似 PCA(programmable counter array)功能．
2.2 Timer2 有三种操作模式：
1. Timer 2 mode
2. Event counter mode
3. Gated timer mode
3
Timer 2 相关缓存器：
Mnemonic
T2CON
CCEN
TL2
TH2
CRCL
CRCH
CCL1
CCH1
CCL2
CCH2
CCL3
CCH3
Description
Direct
Timer 2 control
Compare/Capture
Enable register
Timer 2, low byte
Timer 2, high byte
Compare/Reload/
Capture register,
low byte
Compare/Reload/
Capture register,
high byte
Compare/Capture
register 1, low
byte
Compare/Capture
register 1, high
byte
Compare/Capture
register 2, low
byte
Compare/Capture
register 2, high
byte
Compare/Capture
register 3, low
byte
Compare/Capture
register 3, high
byte
C8h
C1h
CCh
CDh
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Timer 2 and Capture Compare Unit
T2PS CC0FR
T2R[1:0]
COCA COCA
COC
COCA COCA
H3
L3
AH2
L2
H1
TL2[7:0]
TH2[7:0]
CAh
CRCL[7:0]
CBh
CRCH[7:0]
C2h
CCL1[7:0]
C3h
CCH1[7:0]
C4h
CCL2[7:0]
C5h
CCH2[7:0]
C6h
CCL3[7:0]
C7h
CCH3[7:0]
Bit 2
T2CM
COCA
L1
Bit 1
Bit 0
T2I[1:0]
COCA
COC
H0
AL0
RESET
00h
00h
00h
00h
00h
00h
00h
00h
00h
00h
00h
00h
Specifications subject to change without notice, contact your sales representatives for the most recent information.
IRFWX-A094
1
Ver. A 2008/08
SM59R Timer2 功能使用方法
Application Note
Timer 2 and Capture/Compare Unit
Mnemonic: T2CON
7
6
T2PS
CC0FR
5
-
4
3
T2R[1:0]
2
T2CM
1
Address: C8h
0
Reset
T2I[1:0]
00h
T2PS: Prescaler select bit 除频选择
T2PS = 0 – timer 2 频率由系统频率产生，且预除 12
T2PS = 1 – timer 2 频率由系统频率产生，且预除 24
CC0FR: Select active edge:触发缘选择
CC0FR = 0 – 设定为负缘触发
CC0FR = 1 – 设定为正缘触发
T2R[1:0]: Timer 2 reload mode selection 重载模式选择
T2R[1:0] = 0X – 重载禁能
T2R[1:0] = 10 – 模式 0；自动重载模式
T2R[1:0] = 11 – 模式 1
T2CM: Timer 2 Compare mode selection 比较模式选择
T2CM = 0 – 模式 0
T2CM = 1 – 模式 1
T2I[1:0]: Timer 2 input selection 输入选择
T2I[1:0] = 00 – Timer 2 stop 停止
T2I[1:0] = 01 –Timer 2 mode： 输入频率预除 12 或 24
T2I[1:0] = 10 – Event counter mode：输入频率由外部 pin T2 产生 ( T2<=Fosc/2 )
T2I[1:0] = 11 – Gated timer mode：输入频率由 Gate 产生 (pin T2 =1 致能；pin T2=0 禁能)
Mnemonic: CCEN
7
6
COCAH3 COCAL3
5
COCAH2
4
COCAL2
3
COCAH1
2
COCAL1
1
COCAH0
Address: C1h
0
Reset
COCAL0
00h
COCAH3,COCAL3: Compare/capture mode for Channel 3.
COCAH3
COCAL3
Function
0
0
比较 / 捕捉模式禁能
0
1
当 pin CC3 有正缘讯号时，执行捕提模式
1
0
比较模式致能
1
1
当缓存器 CCL3 写入任意值时，执行捕提模式
COCAH2,COCAL2: Compare/Capture mode for Channel 2.
COCAH2
COCAL2
Function
0
0
比较 / 捕捉模式禁能
0
1
当 pin CC2 有正缘讯号时，执行捕提模式
1
0
比较模式致能
1
1
当缓存器 CCL2 写入任意值时，执行捕提模式
Specifications subject to change without notice, contact your sales representatives for the most recent information.
IRFWX-A094
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Ver. A 2008/08
SM59R Timer2 功能使用方法
Application Note
COCAH1,COCAL1: Compare/Capture mode for Channel 1.
COCAH1
COCAL1
Function
0
0
比较 / 捕捉模式禁能
0
1
当 pin CC1 有正缘讯号时，执行捕提模式
1
0
比较模式致能
1
1
当缓存器 CCL1 写入任意值时，执行捕提模式
COCAH0,COCAL0: Compare/Capture mode for CRC register (Channel 0)
COCAH0
COCAL0
Function
0
0
比较 / 捕捉模式禁能
0
1
当 pin CC0 有正缘讯号时，执行捕提模式
1
0
比较模式致能
1
1
当缓存器 CRCL 写入任意值时，执行捕提模式
Timer mode
T2I(Timer 2 input selection)输入选择=[0:1]：
timer 2频率由系统频率Fosc产生，且预除12或24
Event counter mode
T2I(Timer 2 input selection)输入选择=[1:0]：
输入频率由外部pin T2产生 ( T2<=Fosc/2 )
Gated timer mode
T2I(Timer 2 input selection)输入选择=[1:1]：输入频率由Gate产生，pin T2为致能引脚．
pin T2=1，致能gated mode．
pin T2=0，禁能gated mode．
Reload of Timer 2 (Timer 2的重载模式)
重载模式有以下两种：
Mode 0: 每当Timer 2的TH2／TL2溢位，TH2／TL2即会由CRCH／CRCL自动重载(自动重载模式)
Mode 1: 每当 pin T2EX 有一负缘讯号输入，TH2／TL2 即会由 CRCH／CRCL 做一次重载(即 event
mode)；并可由 IEN1 设定，产生外部重载中断(external reload)．
(EXF2: Timer 2 external reload flag, must be cleared by software)
Compare function (Timer 2的比较模式)
四个独立的比较位，SFR TH2／TL2与CCHX／CCLX内容做比较．比较模式可由T2CM选择mode 0
或1，CC0~CC3比较的结果会相对应输出至P1.2~P1.5．
Specifications subject to change without notice, contact your sales representatives for the most recent information.
IRFWX-A094
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Ver. A 2008/08
SM59R Timer2 功能使用方法
Application Note
Compare Mode 0
当设定[COCAHx:COCALx]=[1:0]为比较模式时：
1. 当SFR TH2／TL2等于CCHX／CCLX(或CRCH／CRCL)时，CCx输出为low to high；
2. 当TH2／TL2溢位时，CCx输出为high to low；
3. 此模式对于P1.2~P1.5写入讯号皆是无效的，因输入讯号和写入栓锁器是没有联接的．
Fig. 8-1: Compare mode 0 function
Compare Mode 1
当SFR TH2／TL2等于CCHX／CCLX(或CRCH／CRCL)时，CCx输出会做一次的反相；当TH2／TL2
溢位时状态并不会改变．
Fig. 8-2: Compare mode 1 function
Specifications subject to change without notice, contact your sales representatives for the most recent information.
IRFWX-A094
4
Ver. A 2008/08
SM59R Timer2 功能使用方法
Application Note
4
以下是 Timer 2 中断有关的致能旗标：
Mnemonic
IEN0
IEN1
Description
Interrupt Enable
0 register
Interrupt Enable
1 register
Direct
Bit 7
Bit 6
Bit 5
Interrupt
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
RESET
A8h
EA
-
ET2
ES0
ET1
EX1
ET0
EX0
00h
B8h
EXEN2
-
IEIIC
-
IEEEI
IEADC
IESPI
-
00h
1
ET0
Address: A8h
0
Reset
EX0
00h
Interrupt Enable 0 register(IEN0)
Mnemonic: IEN0
7
6
EA
-
5
ET2
4
ES0
3
ET1
2
EX1
EA: EA = 0 : disable all interrupt.
EA = 1 : enable all interrupt.
ET2: ET2 = 0 : disable Timer 2 overflow or external reload interrupt.
ES0: ES0 = 0 : disable Serial channel 0 interrupt.
ET1: ET1 = 0 : disable Timer 1 overflow interrupt.
EX1: EX1 = 0 : disable external interrupt 1.
ET0: ET0 = 0 : disable Timer 0 overflow interrupt.
EX0: EX0 = 0 : disable external interrupt 0.
Interrupt Enable 1 register(IEN1)
Mnemonic: IEN1
6
7
EXEN2
5
IEIIC
4
-
3
IEEEI
2
IEADC
1
IESPI
Address: B8h
0
Reset
00h
EXEN2: Timer 2 reload interrupt enable
EXEN2 = 0 : disable Timer 2 external reload interrupt.
IEIIC: IIC interrupt enable.
IEIICS = 0 : disable IIC interrupt.
IEEEI: EEI interrupt enable
IEEEI = 0 : disable EEI interrupt
IEADC : A/D converter interrupt enable
IEADC = 0 : disable ADC interrupt.
IESPI: SPI interrupt enable.
IESPI = 0 : disable ISPI interrupt.
Interrupt request register(IRCON)
Mnemonic: IRCON
5
7
6
IICIF
EXF2
TF2
4
-
3
EEIIF
2
ADCIF
1
SPIIF
Address: C0h
0
Reset
00h
EXF2: Timer 2 external reload flag, must be cleared by software.
TF2: Timer 2 overflow flag, must be cleared by software.
IICIF: IIC interrupt flag, must be cleared by software.
EEIIF: EEI interrupt flag, must be cleared by software.
ADCIF: A/D converter interrupt flag, must be cleared by software
SPIIF: SPI interrupt flag, must be cleared by software.
Specifications subject to change without notice, contact your sales representatives for the most recent information.
IRFWX-A094
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Ver. A 2008/08
SM59R Timer2 功能使用方法
Application Note
以下是 Timer 2 相对应的中断向量表：
Table 11-1: Interrupt vectors
IE0 – External interrupt 0
TF0 – Timer 0 interrupt
Interrupt Vector
Address
0003h
000Bh
Interrupt Number
*(use Keil C Tool)
0
1
IE1 – External interrupt 1
0013h
2
TF1 – Timer 1 interrupt
RI0/TI0 – Serial channel 0 interrupt
001Bh
0023h
3
4
TF2/EXF2 – Timer 2 interrupt
SPIIF – SPI interrupt
002Bh
004Bh
5
9
ADCIF – A/D converter interrupt
EEIIF – Expanded External Interrupt
IICIF – IIC interrupt
RI1/TI1 – Serial channel 1 interrupt
0053h
005Bh
006Bh
0083h
10
11
13
16
Interrupt Request Flags
*See Keil C about C51 User’s Guide about Interrupt Function description
Timer 2 中断应用参考程序：
(1) 中断致能设罝：
IEN0 |= 0xA0;
//Enable interrupt All & Timer 2 interrupt
IEN1 |= 0x80;
//Enable Timer 2 external reload interrupt
(2) 中断程序表示：
void T2_interrupt(void) interrupt 5 using 1
{
if(EXF2==1)
{
EXF2=0;
//T2EX - external interrupt
}
if(TF2==1)
{
TF2=0;
//over flow interrupt
}
P2 =~P2;
//detect interrupt freq.
}
Specifications subject to change without notice, contact your sales representatives for the most recent information.
IRFWX-A094
6
Ver. A 2008/08
SM59R Timer2 功能使用方法
Application Note
5
Timer 2 范例程序的流程图:
流程图及范例程序中的设定可参考下表：
Entry SyncMOS
Timer 2 function
< Step1. >
1. MCU init
2. LCD init
< Step2. >
1. ScanKeypad(SW)
2. OSD on LCD
SW = 0~15
False
< SW = 00 >
< SW = 01 >
Ture
．
．
．
．
．
Compare Reload
Mode
Mode
SW
Function
Input sel
descrip.
0
init T2CON
0
1
init T2CON
0
0
internal freq. mode input freq.= Fosc / 12
2
init T2CON
0
1
internal freq. mode input freq.= Fosc / 12
3
init T2CON
1
4
init T2CON
1
0
internal freq. mode input freq.= Fosc / 12
5
init T2CON
1
1
internal freq. mode input freq.= Fosc / 12
6
init T2CON
0
0
Stop
Disable internal freq. mode input freq.= Fosc / 12
Disable internal freq. mode input freq.= Fosc / 12
Stop
7
init T2CON
0
0
Event counter
mode
8
init T2CON
0
0
Gated timer mode
Enable: pin T2 = high;
Disable:pin T2 = low
9
init T2CON
1
1
Gated timer mode
Enable: pin T2 = high;
Disable:pin T2 = low
10
CCx set
write CCHx/CCLx
11
CCx set
write CCHx/CCLx
12
CCEN set
all disable
13
CCEN set
capture at pin CCx edge signal
14
CCEN set
all compare enable
15
CCEN set
capture on write operation into
reg.
CCLx(or CRCL)
External freq. from pin T2
< SW = 14 >
< SW = 15 >
范例程序的操作及量测可参考以下：
No.
User operate
Effect:
Ex1. Reset SW =0：
Timer 2 interrupt 65.535ms
Ex2. Reset SW =1：
Timer 2 interrupt 1ms
Ex3. Reset SW =2 SW =14 SW=10
Timer 2 interrupt 65.535ms
Ex4. Reset SW =2 SW =14 SW=11
Pin CC3 =2ms; CC2 =3ms; CC1 =6ms ; CC0 =10ms;
Timer 2 interrupt 65.535ms
Pin CC3 =10ms; CC2 =6; CC1 =3ms; CC0 =2ms;
Specifications subject to change without notice, contact your sales representatives for the most recent information.
IRFWX-A094
7
Ver. A 2008/08
SM59R Timer2 功能使用方法
Application Note
6
Timer 2 应用的范例程序
Description
Main program
//此范例应用包括 timer 2、LCD 及 4x4 Switch Key 来呈现 timer 2 的过程及结果
//Fosc = internal 12MHz
//====================================================================
//
//
S Y N C M O S T E C H N O L O G Y
//
//====================================================================
#include "..\h\SM59R16A2.h"
#include "..\h\SM59R16A2_ExtraDef.h"
#include "..\MISC\Delay.h"
#include "..\MISC\4x4Keypad.h"
#include "..\LCD\LCD16x2.h"
unsigned char SW = 0x00, int_EXF2 = 0;
unsigned int int_TF2 = 0;
void T2_interrupt(void) interrupt 5 using 1
{
if(TF2==1)
{
TF2=0;
//over flow interrupt
int_TF2++;
}
if(EXF2==1)
{
EXF2=0;
//T2EX - external interrupt
int_EXF2++;
}
P2 =~P2;
//detect interrupt freq.
}
void init_Timer2_T2CON( unsigned char T2_T2PS, unsigned char T2_CC0FR, unsigned
char T2_T2R, unsigned char T2_T2CM, unsigned char T2_T2I )
{
T2CON = 0x00;
T2CON |= (T2_T2PS | T2_CC0FR | T2_T2R | T2_T2CM | T2_T2I);
}
void MCU_init(void)
{
TH2 = 0xEC; //5ms=1us*5000 at 12Mhz/12
TL2 = 0x77;
CRCH = 0XFC;
//1ms=1us*1000 at 12Mhz/12
CRCL = 0x17;
IEN0 |= 0xA0;
//Enable interrupt All & Timer 2 interrupt
IEN1 |= 0x80;
//Enable Timer 2 external reload interrupt
}
void OSD(void)
{
PrintLcdStrLX( 1, 0, "SW:
T2CON: "); //Delay10mSec(1);
Specifications subject to change without notice, contact your sales representatives for the most recent information.
IRFWX-A094
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Ver. A 2008/08
SM59R Timer2 功能使用方法
Application Note
SetCursorAddr(1, 3);
PrintLcdDec(SW);
SetCursorAddr(1,14);
PrintLcdHex(T2CON);
PrintLcdStrLX( 2, 0, "TF2:
SetCursorAddr(2, 4);
PrintLcdHex(int_TF2);
SetCursorAddr(2,14);
PrintLcdHex(int_EXF2);
EXF2: "); //Delay10mSec(1);
}
void main(void)
{
Delay10mSec(2); //wait for system stable
MCU_init();
LCD_Init();
Delay10mSec(2); //wait for LCD init
while(1)
{
SW = ScanKeypad();
OSD();
//fuction set if SW =0~15
//fuction idle if SW =255
//On LCD display
switch(SW)
{
case 0:
init_Timer2_T2CON( T2_CLK12, T2_FALL_EDGE, T2_REL_DIS,
T2_CMP_MODE0, T2_INF );
//1. Timer 2 interrupt 65.535ms
//2. TH2&TL2 count-16bit from 0x0000 to 0xFFFF
//3. if CCEN set compare mode and CCHx/CCLx(or CRC) give value
//
Compare mode 0 CCX will output
break;
case 1:
init_Timer2_T2CON( T2_CLK12, T2_FALL_EDGE, T2_REL_MODE0,
T2_CMP_MODE0, T2_INF );
//Timer 2 interrupt 1ms
//Auto Reload Mode 0:TH2&TL2 will reload from CRCH&CRCL when
overflow
break;
case 2:
init_Timer2_T2CON( T2_CLK12, T2_FALL_EDGE, T2_REL_MODE1,
T2_CMP_MODE0, T2_INF );
//1. Timer 2 interrupt 65.535ms
//2. TH2&TL2 count-16bit from 0x0000 to 0xFFFF
//3. if CCEN set compare mode and CCHx/CCLx(or CRC) give value
//
Compare mode 0 CCX will output
break;
case 3:
init_Timer2_T2CON( T2_CLK12, T2_FALL_EDGE, T2_REL_DIS,
T2_CMP_MODE1, T2_INF );
//Timer 2 interrupt 65.535ms
//TH2&TL2 count-16bit from 0x0000 to 0xFFFF
break;
case 4:
Specifications subject to change without notice, contact your sales representatives for the most recent information.
IRFWX-A094
9
Ver. A 2008/08
SM59R Timer2 功能使用方法
Application Note
init_Timer2_T2CON( T2_CLK12, T2_FALL_EDGE, T2_REL_MODE0,
T2_CMP_MODE1, T2_INF );
//Timer 2 interrupt 1ms
//Auto Reload Mode 0:TH2&TL2 will reload from CRCH&CRCL when
overflow
break;
case 5:
init_Timer2_T2CON( T2_CLK12, T2_FALL_EDGE, T2_REL_MODE1,
T2_CMP_MODE1, T2_INF );
//Timer 2 interrupt 65.535ms
//TH2&TL2 count-16bit from 0x0000 to 0xFFFF
break;
case 6:
init_Timer2_T2CON( T2_CLK12, T2_FALL_EDGE, T2_REL_MODE0,
T2_CMP_MODE0, T2_STOP );
//Timer 2 Stop
break;
case 7:
init_Timer2_T2CON( T2_CLK12, T2_FALL_EDGE, T2_REL_MODE0,
T2_CMP_MODE0, T2_EXF );
//External freq. from pin T2
//Fosc/2 >= pin T2
break;
case 8:
init_Timer2_T2CON( T2_CLK12, T2_FALL_EDGE, T2_REL_MODE0,
T2_CMP_MODE0, T2_GATED );
//if pin T2 = high
// Timer 2 enable
// Timer 2 interrupt 1ms
// Auto-reload
//else if pin T2 = low
// Timer 2 Disable
break;
case 9:
init_Timer2_T2CON( T2_CLK12, T2_FALL_EDGE, T2_REL_MODE1,
T2_CMP_MODE1, T2_GATED );
//if pin T2 = high
// Timer 2 enable
// Timer 2 interrupt 65.535ms
//else if pin T2 = low
// Timer 2 Disable
break;
case 10:
//CCx set
CCH3 = 0xF8;
//2ms
CCL3 = 0x30;
CCH2 = 0xF4;
//3ms
CCL2 = 0x48;
CCH1 = 0xE8;
//6ms
CCL1 = 0x90;
CRCH = 0xD8;
//10ms
CRCL = 0xF0;
break;
case 11:
//CCx set
CCH3 = 0xD8;
//10ms
CCL3 = 0xF0;
CCH2 = 0xE8;
//6ms
CCL2 = 0x90;
Specifications subject to change without notice, contact your sales representatives for the most recent information.
IRFWX-A094
10
Ver. A 2008/08
SM59R Timer2 功能使用方法
Application Note
CCH1 = 0xF4;
CCL1 = 0x48;
CRCH = 0xF8;
CRCL = 0x30;
break;
case 12:
CCEN = 0x00;
break;
case 13:
CCEN = 0x55;
& falling edge at pin CC0
break;
case 14:
CCEN = 0xAA;
break;
case 15:
CCEN = 0xFF;
CCL3/CCL2/CCL1/CRCL
break;
default:
break;
//3ms
//2ms
//all mode disable
//capture on rising edge at pin CC3/CC2/CC1/CC0
//all compare enable, compare mode 0:CCX output
//capture on write operation into register
}
Delay10mSec(8); //SW delay time
}
}
Specifications subject to change without notice, contact your sales representatives for the most recent information.
IRFWX-A094
11
Ver. A 2008/08