msm9223 Oki Semiconductor, msm9223 Datasheet - Page 13

• Manufacturer Part Number: msm9223
• Description: 27-bit Duplex/triplex Vfd Controller/driver With Digital Dimming, Adc And Keyscan
• Manufacturer: Oki Semiconductor

¡ Semiconductor
FUNCTIONAL DESCRIPTION
Power-on Reset
When power is turned on, MSM9223 is initialized by the internal power-on reset circuit.
The status of the internal circuit after initialization is as follows:
• The contents of the shift registers and latches are set to "0".
• The digital dimming duty cycle is set to "0".
• All segment outputs are set to Low level.
• All grid outputs are set to High level.
• All the ROW outputs are set to Low level.
• INT output is set to Low level.
Data Input and Output
Data input and output through the DATA-I/O pin is valid only when the CS pin is set at a High
level.
The input data to DATA I/O pin is shifted into the shift register at the rising edge of the serial
clock. The data is automatically loaded to the latches when the CS pin is set at a Low level.
10-bit dimming data (D1 to D10) and 27-bit segment data (S1 to S27) are used for inputting of
dimming data and display data. To transfer these two data, the mode data (M0 to M2) must be
sent after each of these data succeddingly.
The output data from the DATA I/O pin is output from the shift register at the rising edge of the
serial clock.
MSM9223 outputs 48-bit (6ch ¥ 8bits) A/D data (A11 to A68) and 29-bit key data (S11 to S55, R1
and Q1 to Q3). To receive these data, the mode data (M0 to M2) mast be sent first and then CS
must be set once to Low level and set again to High level.
Then inputting serial clocks, these data are output from the DATA I/O pin.
When the CS pin is set at a Low level, the DATA I/O pin returns to an input pin.
To stop the keyscan, the only mode data (M0 to M2) must be sent. After the mode data transfer,
the key scanning is stopped immediately.
Mode Data
MSM9223 has the seven function modes. The function mode is selected by the mode data (M0 to
M2). The relation between function mode and mode data (M0 to M2) is as follows:
FUNCTION MODE
0
1
2
3
4
5
6
7
Segment Data for GRID1-3 Input
Segment Data for GRID1 Input
Segment Data for GRID2 Input
Segment Data for GRID3 Input
Digital Dimming Data Input
Keyscan Stop
Switch Data Output
A/D Data Output
OPERATING MODE
FUNCTION DATA
M0
0
1
0
1
0
1
0
1
M1
0
0
1
1
0
0
1
1
M2
MSM9223
0
0
0
0
1
1
1
1
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