- 您现在的位置：买卖IC网 > PDF目录69010 > M34238MK-XXXGP 4-BIT, MROM, 4 MHz, MICROCONTROLLER, PDSO20 PDF资料下载
参数资料
| 型号： | M34238MK-XXXGP |
| 元件分类： | 微控制器/微处理器 |
| 英文描述： | 4-BIT, MROM, 4 MHz, MICROCONTROLLER, PDSO20 |
| 封装： | PLASTIC, SOP-20 |
| 文件页数： | 2/41页 |
| 文件大小： | 243K |
| 代理商： | M34238MK-XXXGP |
第1页当前第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
MITSUBISHI MICROCOMPUTERS
4238 Group
SINGLE-CHIP 4-BIT CMOS MICROCOMPUTER for INFRARED REMOTE CONTROL TRANSMITTERS
9
CARR PORT OUTPUT MONITOR TIMER
When the system clock starts oscillating as the system is returned
from a standby state by inputting a rising waveform (from low to high)
________________
to RESET pin, or by pulling the key-on wakeup input pin low, the
CARR port output monitor timer starts up. Then, when the CARR port
output monitor timer reaches 8192 counts of system clock, the pro-
gram counter starts operating. If the port CARR output latch is set to
“1” before the CARR port output monitor timer reaches 72704 counts
of system clock pulses (when instruction clock = f(XIN)/4 selected) af-
ter it starts operating, the CARR port output monitor timer is cleared
to “0” and starts over again beginning with “0”. (Each time the port
CARR output latch is set to “1” with the OCRA instruction, the CARR
port output monitor timer is cleared to “0”.) If the port CARR output
latch is not set to “1” until the CARR port output monitor timer
reaches 72704 counts of system clock, the system enters a standby
state.
Note that the CARR port output monitor timer can neither be read nor
written by software.
Figure 13 shows operation of the CARR port output monitor timer.
Fig. 13 CARR port output monitor timer operation
STANDBY STATE
When the CARR port output monitor timer overflows, the system en-
ters a standby state. In a standby state, the contents of RAM, regis-
ters, and ports are not retained. The oscillator circuit stops operating
and the CPU is placed in its initial state.
The system is returned from a standby state by inputting a rising
____________
waveform (from low to high) to RESET pin, or by pulling the key-on
wakeup input pin low, starting up the program from address 0 in page
0.
RAM BACK-UP STATE
The system enters a RAM back-up state by executing the POF in-
struction. In a RAM back-up state, the contents of RAM is retained,
but the contents of registers and ports are not retained. The oscilla-
tion circuit stops operating and the CPU is placed in its initial state.
The system is returned from a RAM back-up state by pulling the key-
on wakeup input pin low, starting up the program from address 0 in
page 0.
The M34238MK-XXXGP has a flag P to determine whether or not to
return from a RAM back-up state. The flag P is set to “1” only when
the system is returned from a RAM back-up state; it is cleared to “0”
when the system starts up a program after a reset or is returned from
a standby state.
The state of flag P can be examined with the SNZP instruction.
Count value
Program
counter
starts
Program
counter
starts
Program
counter
starts
OCRA instruction
is executed
POF instruction is executed
CARR port output
monitor timer overflows
18ms
(2.25ms)
0
18ms
(2.25ms)
18ms
(2.25ms)
159.8ms
(144ms)
Reset state
RAM back-up state
Standby state
Time
Note : Indicated above are the time and count value when f(XIN) = 455kHz and instruction clock = f(XIN)/4 are selected.
Enclosed in parentheses are the time and count value when f(XIN) = 3.64 MHz and instruction clock = f(XIN)/32 are selected.
72704
(524288)
8192
(8192)
相关PDF资料 |
PDF描述 |
|---|---|
| M34250E2-XXXFP | 4-BIT, OTPROM, 4.4 MHz, MICROCONTROLLER, PDSO20 |
| M34250M2-XXXFP | 4-BIT, MROM, 4.4 MHz, MICROCONTROLLER, PDSO20 |
| M34250M2-XXXFP | 4-BIT, MROM, 4.4 MHz, MICROCONTROLLER, PDSO20 |
| M34280M1-XXXFP | 4-BIT, MROM, 4 MHz, MICROCONTROLLER, PDSO20 |
| M34280M1-XXXGP | 4-BIT, MROM, 4 MHz, MICROCONTROLLER, PDSO20 |
相关代理商/技术参数 |
参数描述 |
|---|---|
| M3424 SL001 | 制造商:Alpha Wire Company 功能描述:CBL 6PR 24AWG SLT 1000' |
| M3424 SL002 | 制造商:Alpha Wire Company 功能描述:CBL 6PR 24AWG SLT 500' |
| M3424 SL005 | 制造商:Alpha Wire Company 功能描述:CBL 6PR 24AWG SLT 100' |
| M3424-0003 | 制造商:Bonitron 功能描述:OVERVOLTAGE BRAKING TRANSISTOR |
| M3424-SL002 | 制造商:Alpha Wire 功能描述: |
发布紧急采购，3分钟左右您将得到回复。