Pin No.TerminalIn/OutFunction
42 , 44, 46 ~ 48,
EA0 ~ EA12OutAddress bus for the effect RAM
51 ~ 59, 61
45ECEBOutChip enable signal output for the effect RAM
49EOEBOutRead enable signal output for the effect RAM
50VSS3InGround (0 V) source
60EWEBOutWrite enable signal output for the effect RAM
62, 66, 70, 74, 78VSS2InGround source
63, 67, 71, 75, 79VDD2In+5 V source
64, 65, 68, 69,
PA0 ~ PA5OutButton scan signal output
72, 73
76, 77PA6/7OutNot used
LCD DRIVER (LSI401: SED1278F2A)
The LCD driver can drive a dot matrix LCD having 40 segment and 16 common lines. The LSI contains 240
graphic symbols in the built-in character generator ROM, and stores 80 characters in the built-in display data
RAM. In accordance with command from the CPU, the LSI is capable of displaying up to 16 characters
simultaneously. The following table shows the pin functions of LSI 401.
Pin No.TerminalIn/OutFunction
1 ~ 22,
SEG1 ~ SEG40OutSegment signal output
63 ~ 80
23VSSNGND (0 V) source
Terminals for the built-in clock pulse generator. The external
24, 25OSC1, OSC2In/Out
resistor connected determines the oscillation frequency.
LCD drive voltage input.
26 ~ 30V1 ~ V5InThose voltages are used for generating the stepped pulse of
the LCD drive signals.
31, 32LP, XCLSNNot used
33VDDInDVDD (+5 V) source
34, 35FR, DONNot used
Data/command determination terminal.
36RSIn
High: data, Low: command
37R/WInRead/write terminal. High: read, Low: write
Chip enable signal.
38EInHigh: enable, the writing is done at fall edge.
Low: disenable
39 ~ 42DB0 ~ DB3NNot used. Connected to GND (0 V)
43 ~ 46DB4 ~ DB7In/OutData bus
47 ~ 62COM1 ~ COM16OutCommon signal/output
N 8 N |
ACEC
