hd66765 Renesas Electronics Corporation., hd66765 Datasheet - Page 28

• Manufacturer Part Number: hd66765
• Description: 396-channel Segment Driver With Internal Ram For 4096-color Displays - Hitachi Semiconductor
• Manufacturer: Renesas Electronics Corporation.

Horizontal RAM Address Position (R16h)
Vertical RAM Address Position (R17h)
HSA7-0/HEA7-0: Specify the horizontal start/end positions of a window for access in memory. Data can
be written to the GRAM from the address specified by HEA7-0 from the address specified by HSA7-0.
Note that an address must be set before RAM is written to. Ensure 00h HSA7-0 HEA7-0 3Fh.
VSA7-0/VEA7-0: Specify the vertical start/end positions of a window for access in memory. Data can be
written to the GRAM from the address specified by VEA7-0 from the address specified by VSA7-0. Note
that an address must be set before RAM is written to. Ensure 00h VSA7-0 VEA7-0
R/W
W
W
VSA
VEA
Note:
RS
1
1
0000h
HEA7
VEA7
DB15
1. Ensure that the window address area is within the GRAM address space.
2. In high-speed write mode, data are written to GRAM in four-words.
Figure 17 Horizontal/Vertical RAM Address Position Instruction
Thus, dummy write operations should be inserted depending on the window address
area. For details, see the High-Speed Burst RAM Write Function section.
HEA6
VEA6
DB14
HSA
GRAM address space
HEA5
VEA5
DB13
Window address
Figure 18 Window Address Setting Range
HEA4
VEA4
DB12
HEA3
VEA3
DB11
HEA2
VEA2
DB10
HEA
HEA1
VEA1
DB9
28
AF83h
HEA0
VEA0
DB8
HSA7
VSA7
DB7
Window address setting range
"00"h
"00"h
HSA6
VSA6
DB6
HSA5
VSA5
DB5
HSA7-0
VSA7-0
HSA4
VSA4
DB4
VEA7-0
HSA3
HEA7-0
VSA3
DB3
HSA2
VSA2
AFh.
DB2
HD66765
"AF"h
"83"h
HSA1
VSA1
DB1
HSA0
VSA0
DB0