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SOLOMON
SSD1820A/21
21
REV 1.4
01/03
tional Description.
To write data to the GDDRAM, input Low to R/W(WR) pin and High to D/ C pin for 6800-series parallel mode. For serial interface, it will
always be in write mode. GDDRAM column address pointer will be increased by one automatically after each data write. The address will
be reset to 0 in next data read/write operation is executed when it is 127.
Address Increment Table (Automatic)
Address Increment is done automatically after data read/write. The column address pointer of GDDRAM is also affected. It will be reset
to 0 in next data read/write operation is executed when it is 127.
Commands Required for R/W(WR) Actions on RAM
* No need to resend the command again if it is set previously.
The read / write action to the Display Data RAM does not depend on the display mode. This means the user can change the RAM content
whether the target RAM content is being displayed or not.
D/ C
R/W(WR)
Comment
Address Increment
0
0
Write Command
No
0
1
Read Status
No
1
0
Write Data
Yes
1
1
Read Data
Yes
R/W(WR) Actions on RAMs
Commands Required
Read/Write Data from/to GDDRAM.
Set GDDRAM Page Address
Set GDDRAM Column Address
Read/Write Data
(1011X3X2X1X0)*
(0001X3X2X1X0)*
(0000X3X2X1X0)*
(X 7X6X5X4X3X2X1X0)