参数资料
型号: M37545G4-XXXGP
元件分类: 微控制器/微处理器
英文描述: 8-BIT, MROM, 4 MHz, MICROCONTROLLER, PQFP32
封装: 7 X 7 MM, 0.80 MM PITCH, PLASTIC, LQFP-32
文件页数: 25/65页
文件大小: 782K
代理商: M37545G4-XXXGP
Rev.1.07
Mar 19, 2009
Page 29 of 60
REJ03B0140-0107
7545 Group
4. Carrier wave generating circuit
The carrier wave generating circuit is used to generate the control
wave of the remote control by using timer 2 and timer 3 (Figure
In order to use the carrier wave generating function by timer 2,
set “1” to the carrier wave output valid bit (bit 1 of the carrier
wave control register (address 2716)).
Carrier wave “H” duration is set to the timer 2 primary, and
carrier wave “L” duration is set to the timer 2 secondary. Timer 2
counts a primary latch and a secondary latch alternately, and
controls carrier wave “H” duration and the “L” duration (Figure
The “H” duration of the carrier waveform can be expanded for a
half clock of timer 2 count source by setting “1” to the carrier
wave “H” duration bit (bit 0) (Figure 28).
Therefore, the frequency of the carrier wave can be set by the
resolution of 1/2 of the timer 2 count source.
For example, the carrier wave of the resolution of 125 ns (max.)
can be generated at f(XIN) = 4 MHz when f(XIN)/1 is selected for
the timer 2 count source.
In order to initialize the carrier waveform, write in the timer 2
primary after stopping the count of timer 2, and then, start the
count of timer 2. The output of the carrier waveform is started
from a primary period.
Output/stop of the carrier waveform can be controlled by
software or timer 3 (Figure 31 and Figure 32). The output of the
carrier wave is started from the P42/CARR pin when “1” is set to
the software carrier wave output bit (bit 2), and the output of the
carrier wave is stopped when “0” is written.
The auto-output of the carrier wave using timer 3 can be
performed by setting “1” to the carrier wave auto-output control
bit (bit 3) (Figure 29). Each time timer 3 underflow occurs, the
trigger signal which is used to turn the output of the carrier wave
on/off is generated.
The trigger from timer 3 becomes valid by setting “1” to the
carrier wave output trigger bit (bit 4), and the output/stop of the
carrier wave from the P42/CARR pin is repeated each time timer
3 underflows. Timer 3 count continues without stopping though
the output/stop state of the carrier wave at that time is maintained
when “0” is written to the carrier wave auto-output control bit
(bit 3) while the output of the carrier wave by timer 3 is
controlled.
In order to initialize output/stop control of the carrier waveform,
write in the timer 3 after stopping the count of timer 3, and then,
start the count of timer 3. The output of the carrier waveform is
started from “waveform output valid period”.
5. 455 kHz carrier wave generating mode
The 455 kHz carrier wave generating mode is used to generate
artificially the 455 kHz carrier wave by auto-control of the
setting value of the timer, or the waveform expansion mode.
If “1” (valid) is set to the 455 kHz carrier wave generating mode
bit (bit 5), the values of the timer latch and the carrier wave “H”
duration expansion bit (bit 0) are automatically set.
Then, the nine waveforms of 2.250
s wavelength and the seven
waveforms of 2.125
s wavelength are generated periodically as
shown in Figure 30.
The carrier wave of 455.516 kHz can be pseudo generated since
the average wavelength for one period becomes 2.195
s.
In order to use 455 kHz carrier wave generating mode, use the 4
MHz oscillator and select f(XIN)/1 for the timer 2 count source.
Fig. 25 Carrier wave control register
b7
b0
Carrier wave control register
(CARCNT : address 002716, initial value: 0016)
Carrier wave “H” duration expansion bit
0: “H” duration expansion function invalid
1: “H” duration expansion function valid
Disable (return “0” when read)
Carrier wave output valid bit
0: Carrier wave generating function invalid
1: Carrier wave generating function valid
Software carrier wave output bit
0: Output invalid
1: Output valid
Carrier wave auto-output control bit
0: Auto-control by timer 3 invalid
1: Auto-control by timer 3 valid
Carrier wave output trigger bit
0: Carrier wave output trigger invalid
1: Carrier wave output trigger valid
455 kHz carrier wave generating mode bit
0: 455 kHz carrier wave generating mode
invalid
1: 455 kHz carrier wave generating mode
valid
Carrier wave output level bit
0: Positive waveform
1: Inverted waveform
相关PDF资料
PDF描述
M37545G4KP 8-BIT, MROM, 4 MHz, MICROCONTROLLER, PDSO32
M37546G4SP 8-BIT, MROM, 8 MHz, MICROCONTROLLER, PDIP32
M30201F6FP 16-BIT, FLASH, 10 MHz, MICROCONTROLLER, PQFP56
M30201F6TFP 16-BIT, FLASH, 10 MHz, MICROCONTROLLER, PQFP56
MB90543GSPMC 16-BIT, MROM, 16 MHz, MICROCONTROLLER, PQFP100
相关代理商/技术参数
参数描述
M37545G6GP 制造商:RENESAS 制造商全称:Renesas Technology Corp 功能描述:SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
M37545G6GP#U0 功能描述:MCU 3/5V 24K 32-LQFP QZ-ROM RoHS:是 类别:集成电路 (IC) >> 嵌入式 - 微控制器, 系列:740/38000 标准包装:250 系列:80C 核心处理器:8051 芯体尺寸:8-位 速度:16MHz 连通性:EBI/EMI,I²C,UART/USART 外围设备:POR,PWM,WDT 输入/输出数:40 程序存储器容量:- 程序存储器类型:ROMless EEPROM 大小:- RAM 容量:256 x 8 电压 - 电源 (Vcc/Vdd):4.5 V ~ 5.5 V 数据转换器:A/D 8x10b 振荡器型:内部 工作温度:-40°C ~ 85°C 封装/外壳:68-LCC(J 形引线) 包装:带卷 (TR)
M37545G6KP 制造商:RENESAS 制造商全称:Renesas Technology Corp 功能描述:SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
M37545G6-XXXGP 制造商:RENESAS 制造商全称:Renesas Technology Corp 功能描述:SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
M37545G8GP 制造商:RENESAS 制造商全称:Renesas Technology Corp 功能描述:SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER