Renesas F-ZTAT H8 Series Hardware Manual page 371

Examples of display data register (LR4) read/write access when read-modify-write is
designated are shown below.
[Set index register to display data register]
• Port A set to output mode, RMW set to 1
MOV.W #H'0100,R1
MOV.W #H'04FF,R0
R1L,@PDRA ............. Clear R/W to 0
MOV.B
MOV.B R0H,@PDR9
R0L,@PCR9 ............. Output H'04 from port 9
MOV.B
MOV.B R1H,@PDRA
R1L,@PDRA ............. Write H'04 to index register
MOV.B
[Read display data register]
R1L,@PCR9 ............. Set port 9 to input mode
MOV.B
MOV.W #H'0706, R2
R2L,@PDRA ............. Set R/W to 1
MOV.B
MOV.B R2H,@PDRA
@PDR9, R0H ............ Read PDR9 into general register
MOV.B
MOV.B R2L,@PDRA
[Write to display data register]
MOV.W #H'0504,R3
R3L,@PDRA ............. Clear R/W to 0
MOV.B
NOT.B R0H
MOV.B R0H,@PDR9
R0L,@PCR9 ............. Set port 9 to output mode
MOV.B
MOV.B R3H,@PDRA
R3L @PDRA ............. Write data to display data register
MOV.B
............. Invert general register data
13. Dot Matrix LCD Controller (H8/3857 Group)
Rev.3.00 Jul. 19, 2007 page 345 of 532
REJ09B0397-0300