S6A0074 Datasheet, PDF (40/68 Pages) Samsung semiconductor – 34COM/80SEG DRIVER & CONTROLLER FOR DOT MATRIX LCD

S6A0074
34COM/80SEG DRIVER & CONTROLLER FOR DOT MATRIX LCD
Read Busy Flag & Address
RS
R/W
DB7
DB6
DB5
DB4
DB3
DB2
DB1
DB0
0
1
BF
AC6
AC5
AC4
AC3
AC2
AC1
AC0
This instruction shows whether S6A0074 is in internal operation or not. If the resultant BF is High, it means the
internal operation is in progress and you have to wait until BF to be low, and then the next instruction can be
performed. In this instruction you can read also the value of address counter.
Write Data to RAM
RS
R/W
DB7
DB6
DB5
DB4
DB3
DB2
DB1
DB0
1
0
D7
D6
D5
D4
D3
D2
D1
D0
Write binary 8-bit data to DDRAM/CGRAM/SEGRAM.
The selection of RAM from DDRAM, CGRAM, or SEGRAM, is set by the previous address set instruction :
DDRAM address set, CGRAM address set, SEGRAM address set. RAM set instruction can also determines the
AC direction to RAM. After write operation, the address is automatically increased/decreased by 1, according to
the entry mode.
Read Data From RAM
RS
R/W
DB7
DB6
DB5
DB4
DB3
DB2
DB1
DB0
1
1
D7
D6
D5
D4
D3
D2
D1
D0
Read binary 8-bit data from DDRAM/CGRAM/SEGRAM.
The selection of RAM is set by the previous address set instruction. If address set instruction of RAM is not
performed before this instruction, the data that read first is invalid, because the direction of AC is not determined.
If you read RAM data several times without RAM address set instruction before read operation, you can get
correct RAM data from the second, but the first data would be incorrect, because there is no time margin to
transfer RAM data. In case of DDRAM read operation, cursor shift instruction plays the same role as DDRAM
address set instruction : it also transfer RAM data to output data register. After read operation address counter is
automatically increased/decreased by 1 according to the entry mode. After CGRAM/SEGRAM read operation,
display shift may not be executed correctly.
- In case of RAM write operation, after this AC is increased/decreased by 1 like read operation. In this time, AC
indicates the next address position, but you can read only the previous data by read instruction.
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