Setting Transfer Rate Of Serial Interface; Setting Clock For Lcd Driver Display Timing Generator - Epson S1C88655 Technical Manual

13 PROGRAMMABLE TIMER

13.7 Setting Transfer Rate of Serial Interface

The underflow signals of Timer 1 and Timer 7 can
be used as the source clock for serial interface Ch.
0 and Ch.1, respectively. The transfer rate is set
using the registers PST1x and RDR1x for Ch. 0 or
PST7x and RDR7x for Ch. 1. (since only the
underflow signal is used as the serial interface
clock source, the CDR1x or CDR7x register value
does not affect the transfer rates. It can be set to
any value).
Transfer rate f
OSC3
(bps) PST1x
PST7x
19,200
9,600
4,800
2,400
1,200
600
300
150
∗ Since the underflow signal only is used as the clock source, the CDR1x
or CDR7x register value does not affect the transfer rates.

13.8 Setting Clock for LCD Driver Display Timing Generator

The underflow signal of Timer 5 can be used as the
source clock for the display timing generator in the
LCD driver. This makes it possible to set the frame
frequency minutely.
The frequency is set up using the registers PST5x
and RDR5x (since only the underflow signal is used
as the source clock, the CDR5x register value does
not affect the frame signal. It can be set to any
value).
The Timer 5 underflow signal is divided by 2 before
supplying to the display timing generator, so set a
value represented by the following expressions to
the register RDR5x.
104
Table 13.7.1 Example of transfer rate setting
OSC3 oscillation frequency / Programmable timer settings
= 2.4576 MHz f
OSC3
RDR1x PST1x
RDR7x PST7x
00H 03H 00H
00H 07H 00H
00H 0FH 00H
00H 1FH 00H
00H 3FH 00H
00H 7FH 00H
02H 1FH 03H
02H 3FH 03H
Since the underflow signal of Timer is divided by
32 in the serial interface, the value set in the
register RDR1x or RDR7x which corresponds to
the transfer rate is shown in the following expres-
sion:
RDR = ————— - 1
32 × bps
RDR: RDR1x or RDR7x set value
fdiv: Input clock frequency
(setting of PST1x or PST7x)
bps: Transfer rate
= 3.0720 MHz f = 3.6864 MHz
OSC3
RDR1x PST1x
RDR7x PST7x
04H 00H
09H 00H
13H 00H
27H 00H
4FH 00H
9FH 00H
09H 01H
13H 02H
RDR5x = —————— - 1
or
RDR5x = —————— - 1
fdiv: Input clock frequency (setting of PST5x)
f : Display timing generator source clock
CL
frequency (Hz)
f : Frame frequency (Hz)
FR
EPSON
fdiv
f = 4.3008 MHz
OSC3
RDR1x PST1x RDR1x
RDR7x PST7x RDR7x
05H 00H 06H
0BH 00H 0DH
17H 00H 1BH
2FH 00H 37H
5FH 00H 6FH
BFH 00H DFH
BFH 01H DFH
5FH 02H 6FH
fdiv
2 × f
CL
fdiv
2 × 64 × f
FR
S1C88655 TECHNICAL MANUAL