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ML9041
Built–in Reset Circuit
The ML9041 is automatically initialized when the power is turned on.
During initialization, the Busy Flag (BF) is “1” and the ML9041 does not accept any instruction
from the CPU (other than the Read BF instruction).
The Busy Flag is “1” for about 15 ms after the V becomes 2.5 V or higher.
DD
During this initialization, the ML9041 performs the following instructions:
1) Display clearing
2) CPU interface data length = 8 bits
3) 1–line LCD display
4) Font size = 5 ¥ 7 dots
5) ADC counting = Increment
6) Display shifting = None
7) Display = Off
8) Cursor = Off
9) Blinking = Off
10) Arbitrator = Displayed in the lower line
(DL = “1”)
(N = “0”)
(F = “0”)
(I/D = “1”)
(S = “0”)
(D = “0”)
(C = “0”)
(B = “0”)
(AS = “0”)
11) Setting 1FH (hexadecimal) to the Contrast Data
To use the built–in reset circuit, the power supply conditions shown below should be satisfied.
Otherwise, thebuilt–inresetcircuitmaynotworkproperly. Insuchacase, initializetheML9041
withtheinstructionsfromtheCPU. Theuseofabatteryalwaysrequiressuchinitializationfrom
the CPU. (See “Initial Setting of Instructions”)
2.5V
0.2V
0.2V
0.2V
tON
tOFF
1ms£ tOFF
0.1ms£ tON £ 100ms
Figure 1 Power–on and Power–off Waveform
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