HD61830 Datasheet, PDF (14/43 Pages) Hitachi Semiconductor – LCDC (LCD Timing Controller)

HD61830/HD61830B
8. Write Display Data: (Execution time: 6 µs) After the code $“0C” is written into the instruction register
with RS = 1, 8-bit data with RS = 0 should be written into the data register. This data is transferred to the
RAM specified by the cursor address as display data or character code. The cursor address is increased by 1
after this operation.
Register
Instruction reg.
RAM
R/W RS DB7 DB6 DB5 DB4 DB3 DB2 DB1 DB0
0
1
0
0
0
0
1
1
0
0
0
0
MSB (pattern data, character code) LSB
9. Read Display Data: (Execution time: 6 µs) Data can be read from the RAM with RS = 0 after writing
code $“0D” into the instruction register. Figure 1 shows the read procedure.
This instruction outputs the contents of data output register on the data bus (DB0 to DB7) and then
transfers RAM data specified by the cursor address to the data output register, also increasing the cursor
address by 1. After setting the cursor address, correct data is not output at the first read but at the second
one. Thus, make one dummy read when reading data after setting the cursor address.
Register
Instruction reg.
RAM
R/W RS DB7 DB6 DB5 DB4 DB3 DB2 DB1 DB0
0
1
0
0
0
0
1
1
0
1
1
0
MSB (pattern data, character code) LSB
CS
E
R/W
RS
DB
Cursor
address
B 0A N_L B OB N_U B
Busy Cursor Cursor
check address low
set
order
mode address
write
Busy
check
Cursor Cursor
address high
set
order
mode address
write
Busy
check
N_L
0D *
B (N) B ^(N+1)
Data
read
mode
Dummy
read
Busy
check
N
address
data
read
Busy
check
N+1
address
data
read
N
N+1
N+2 N+3
Data output
register
N address data N + 1 address data N + 2 ^...
Figure 1 Read Procedure
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