hd66789 Renesas Electronics Corporation., hd66789 Datasheet - Page 110

• Manufacturer Part Number: hd66789
• Description: 528-channel, One-chip Driver For Amorphous Tft Panels With 262,144-color Display Ram, Power Supply Circuit, And Gate Circuit
• Manufacturer: Renesas Electronics Corporation.

HD66789
4. Write mode 4: AM = 1, LG2–0 = 110/111
This mode is used when data are horizontally written with comparing the write data and the value set in the
compare register (CP17–0) by R, G, B pixel. When the result of the comparison satisfies a condition, the
write data sent from the microcomputer are written to GRAM. The write-data mask function (WM17–0) is
also available with this mode. After writing, the address counter (AC) automatically increments by 256,
and automatically jumps to the counter either at the top of the next right row (ID = 1) or at the top of the
next left row (I/D = 0) according to the setting in the I/D bit, when the address reaches the bottom of
GRAM.
Rev.0.12, May 09 2003, page 110 of 156
Compare register:
Write-data mask:
Write-data (2):
Write-data (1):
"0000"H
"0100"H
"EF00"H
Operation example
1) I/D = "1", AM = "1", LG2-0 = "111" (unmatched writing)
2)CP17-0 = "0A0C0"H
3)WM17-0 = "00000"H
4) AC = "0000"H
Note 1) The bits in the GRAM with “ * ” are not overwritten.
Note 2) After writing data to the address "EF00"H, the address counter jumps to
DB17
0 0 0
0 0 1
1 0 0
0 0 1
* * *
CP17
0 0 1
WM17
Data are expanded into 18 bits in 8/16-bit system
interface, and 16-bit RGB interface modes.
"0001"H.
0
0
1
0
*
0
0 0
1 0
1 1
1 0
* *
0 1
0
0
0
0
1
*
"0000"H
( Unmatched)
0
0
0
0
*
0
(Matched)
0
0
1
0
0
*
0
0
1
0
*
1
0
1
0
1
1
*
0 0
1 0
0 1
1 0
* *
0 0
Write Mode 4
0
0
1
0
*
1
0 0
0 0
1 1
0 0
1 1
* *
Compare
operation
CP0
0
0
1
0
*
WM0
1
DB0
0
0
1
0
1
*
Write-data (1)
Write-data (2)
C
Compare operation
GRAM
"0100"H
C
Conditional replacement
Conditional replacement
R
R
1 0 0
* * *
1
*
1 1
* *
Replacement
0
*
0
*
1
*
1
*
0
*
0 1
* *
1
*
1 1
* *
Preliminary
1
*
1
*