- 您现在的位置：买卖IC网 > PDF目录98144 > ST72311N4T6/XXX (STMICROELECTRONICS) 8-BIT, MROM, 8 MHz, MICROCONTROLLER, PQFP64 PDF资料下载
参数资料
| 型号： | ST72311N4T6/XXX |
| 厂商： | STMICROELECTRONICS |
| 元件分类： | 微控制器/微处理器 |
| 英文描述： | 8-BIT, MROM, 8 MHz, MICROCONTROLLER, PQFP64 |
| 封装： | PLASTIC, TQFP-64 |
| 文件页数： | 33/92页 |
| 文件大小： | 624K |
| 代理商： | ST72311N4T6/XXX |
第1页第2页第3页第4页第5页第6页第7页第8页第9页第10页第11页第12页第13页第14页第15页第16页第17页第18页第19页第20页第21页第22页第23页第24页第25页第26页第27页第28页第29页第30页第31页第32页当前第33页第34页第35页第36页第37页第38页第39页第40页第41页第42页第43页第44页第45页第46页第47页第48页第49页第50页第51页第52页第53页第54页第55页第56页第57页第58页第59页第60页第61页第62页第63页第64页第65页第66页第67页第68页第69页第70页第71页第72页第73页第74页第75页第76页第77页第78页第79页第80页第81页第82页第83页第84页第85页第86页第87页第88页第89页第90页第91页第92页
39/92
ST72311
16-BIT TIMER (Cont’d)
4.3.3.4 Output Compare
In this section, the index,
i, may be 1 or 2.
This function can be used to control an output
waveform or indicating when a period of time has
elapsed.
When a match is found between the Output Com-
pare register and the free running counter, the out-
put compare function:
– Assigns pins with a programmable value if the
OCIE bit is set
– Sets a flag in the status register
– Generates an interrupt if enabled
Two 16-bit registers Output Compare Register 1
(OC1R) and Output Compare Register 2 (OC2R)
contain the value to be compared to the free run-
ning counter each timer clock cycle.
These registers are readable and writable and are
not affected by the timer hardware. A reset event
changes the OCiR value to 8000h.
Timing resolution is one count of the free running
counter: (
fCPU/(CC1.CC0)).
Procedure
To use the output compare function, select the fol-
lowing in the CR2 register:
– Set the OC
iE bit if an output is needed then the
OCMP
i pin is dedicated to the output compare i
function.
– Select the timer clock (CC1-CC0) (see Table
15).
And select the following in the CR1 register:
– Select the OLVL
i bit to applied to the OCMPi pins
after the match occurs.
– Set the OCIE bit to generate an interrupt if it is
needed.
When a match is found:
– OCF
i bit is set.
– The OCMP
i pin takes OLVLi bit value (OCMPi
pin latch is forced low during reset and stays low
until valid compares change it to a high level).
– A timer interrupt is generated if the OCIE bit is
set in the CR2 register and the I bit is cleared in
the CC register (CC).
Clearing the output compare interrupt request is
done by:
1. Reading the SR register while the OCF
i bit is
set.
2. An access (read or write) to the OC
iLR register.
Note: After a processor write cycle to the OC
iHR
register, the output compare function is inhibited
until the OC
iLR register is also written.
If the OC
iE bit is not set, the OCMPi pin is a gen-
eral I/O port and the OLVL
i bit will not appear
when a match is found but an interrupt could be
generated if the OCIE bit is set.
The value in the 16-bit OCiR register and the OLV
i
bit should be changed after each successful com-
parison in order to control an output waveform or
establish a new elapsed timeout.
When the clock is divided by 2, OCF
i and OCMPi
are set while the counter value equals the OC
iR
register value (see Figure 29, on page 40). This
behaviour is the same in OPM or PWM mode.
When the clock is divided by 4, 8 or in external
clock mode , OCF
i and OCMPi are set while the
counter value equals the OC
iR register value plus
1 (see Figure 30, on page 40).
The OCiR register value required for a specific tim-
ing application can be calculated using the follow-
ing formula:
Where:
t
= Desired output compare period (in
seconds)
fCPU
= Internal clock frequency
tPRESC = Timer clock prescaler (CC1-CC0 bits,
see Table 15)
The following procedure is recommended to pre-
vent the OCF
i bit from being set between the time
it is read and the write to the OCiR register:
– Write to the OC
iHR register (further compares
are inhibited).
– Read the SR register (first step of the clearance
of the OCF
i bit, which may be already set).
– Write to the OC
iLR register (enables the output
compare function and clears the OCF
i bit).
MS Byte
LS Byte
OC
iROCiHR
OC
iLR
OCiR=
t * fCPU
tPRESC
39
相关PDF资料 |
PDF描述 |
|---|---|
| ST72311J2B6/XXX | 8-BIT, MROM, 8 MHz, MICROCONTROLLER, PDIP42 |
| ST72311N2T3/XXX | 8-BIT, MROM, 8 MHz, MICROCONTROLLER, PQFP64 |
| ST72321BAR7T6 | MICROCONTROLLER, QFP64 |
| ST72321BR7T3 | MICROCONTROLLER, QFP64 |
| ST72321M9T3/XXX | 8-BIT, MROM, MICROCONTROLLER, PQFP80 |
相关代理商/技术参数 |
参数描述 |
|---|---|
| ST72311N5B6 | 制造商:未知厂家 制造商全称:未知厂家 功能描述:8-Bit Microcontroller |
| ST72311N6B6 | 制造商:未知厂家 制造商全称:未知厂家 功能描述:8-Bit Microcontroller |
| ST72311R | 制造商:STMICROELECTRONICS 制造商全称:STMicroelectronics 功能描述:8-BIT MCU WITH NESTED INTERRUPTS, EEPROM, ADC, 16-BIT TIMERS, 8-BIT PWM ART, SPI, SCI, CAN INTERFACES |
| ST72311R4Q6 | 制造商:未知厂家 制造商全称:未知厂家 功能描述:8-Bit Microcontroller |
| ST72311R5Q6 | 制造商:未知厂家 制造商全称:未知厂家 功能描述:8-Bit Microcontroller |
发布紧急采购，3分钟左右您将得到回复。