HD66766R Datasheet, PDF (30/97 Pages) Hitachi Semiconductor – 132 x 176-dot Graphics LCD Controller/Driver for 65K Colors

HD66766R
Rev. 1.0-1 / September 2002
Frame Cycle Control (R0Bh)
R/W RS DB15 DB14 DB13 DB12 DB11 DB10 DB9 DB8 DB7 DB6 DB5 DB4 DB3 DB2 DB1 DB0
W 1 0 0 0 0 0 0 DIV1 DIV0 0 0 0 0 RTN3 RTN2 RTN1 RTN0
Figure 15
RTN3-0: Set the line retrace period (RTN3-0) to be added to raster-row cycles. The raster-row cycle
becomes long according to the number of clocks set at RTN3-0.
DIV1-0: Set the division ratio of clocks for internal operation (DIV1-0). Internal operations are driven
by clocks which are frequency divided according to the DIV1-0 setting. Frame frequency can be
adjusted along with the line retrace period (RTN3-0). When changing the drive-duty, adjust the frame
frequency. For details, see the Frame Frequency Adjustment Function section.
Table 21 RTN Bits and Clock Cycles
RTN3 RTN2 RTN1 RTN1
0
0
0
0
0
0
0
1
0
0
1
0
0
0
1
1
:
:
:
:
1
1
1
0
1
1
1
1
Line retrace period
(Clock Cycles)
0 clock
1 clock
2 clock
3 clock
:
14 clock
15 clock
Clock Cycles per
one raster-row
26 clock
27 clock
28 clock
29 clock
:
40 clock
41 clock
Table 22 DIV Bits and Clock Frequency
DIV1 DIV0
0
0
0
1
1
0
1
1
Division ratio
Internal Operation
Clock Frequency
1
fosc / 1
2
fosc / 2
4
fosc / 4
8
fosc / 8
* fosc=R-C oscillation frequency
Formula for the frame frequency
Frame frequency =
fosc
[Hz]
Clock cycles per raster-row xdivision ratio x 1/duty cycle
fosc: RC oscillation frequency
Duty: Drive duty (NL bit)
Division ratio: DI V bit
Clock cycles per raster-row: (RTN+26) clock
30