Datasheet

ST7735
V1.7 104 2009-12-04
10.1.22 RAMRD (2Eh): Memory Read
2EH RAMHD (Memory Read)
Inst / Para D/CX WRX RDX D17-8 D7 D6 D5 D4 D3 D2 D1 D0 HEX
RAMHD 0 ↑ 1 - 0 0 1 0 1 1 1 0 (2Eh)
1
st
parameter 1 1 ↑ - - - - - - - - -
2
nd
parameter 1 1 ↑ D17-8 D7 D6 D5 D4 D3 D2 D1 D0
∣ 1 1 ↑ ∣ ∣ ∣ ∣ ∣ ∣ ∣ ∣ ∣
(N+1)th parameter 1 1 ↑ D17-8 D7 D6 D5 D4 D3 D2 D1 D0
Description
-This command is used to transfer data from frame memory to MCU.
-When this command is accepted, the column register and the row register are reset to the Start Column/Start
Row positions.
-The Start Column/Start Row positions are different in accordance with MADCTL setting.
-Then D[17:0] is read back from the frame memory and the column register and the row register incremented as
section 9.10
-Frame Read can be cancelled by sending any other command.
-The data color coding is fixed to 18-bit in reading function. Please see section 9.8 “Data color coding” for color
coding (18-bit cases), when there is used 8, 9, 16 and 18-bit data lines for image data.
Note1: The Command 3Ah should be set to 66h when reading pixel data from frame memory.Please check the
LUT in chapter 9.17 when using memory read function.
Default
Status Default Value
Power On Sequence Contents of memory is set randomly
S/W Reset Contents of memory is not cleared
H/W Reset Contents of memory is not cleared
Flow Chart