Function; Serial Clock; Clock Source - Philips CEM2100/00 Service Manual

14. Synchronous Serial Interface (SIO1)

14.3 Function

14.3 Function

14.3.1 Serial clock

14.3.1.1 Clock source

instruction to SIO1CR<SCK> should be executed while the transfer is stopped (when SIO1SR<SIOF>
"0")
SIO1CR<SIOS>
pin output
SCK1
SO1 pin
SIO1TDB
Figure 14-2 Automatic-wait Function (Example of transmit mode)
Table 14-1 Serial Clock Rate (fc = 16 MHz, fs = 32.768kHz)
SCK
000
001
010
011
100
101
110
The serial clock can be selected by using SIO1CR<SCK>. When the serial clock is changed, the writing
(1) Internal clock
Setting the SIO1CR<SCK> to other than "111B" outputs the clock (shown in " Table 14-1 Serial
Clock Rate (fc = 16 MHz, fs = 32.768kHz) ") as serial clock outputs from
beginning or finishing of a transfer,
When writing (in the transmit mode) or reading (in the receive mode) data can not follow the serial
clock rate, an automatic-wait function is executed to stop the serial clock automatically and hold the
next shift operation until reading or writing is completed (shown in " Figure 14-2 Automatic-wait
Function (Example of transmit mode) "). The maximum time from releasing the automatic-wait
function by reading or writing a data is 1 cycle of the selected serial clock until the serial clock comes
out from pin.
SCK1
A7 A6 A5
A
NORMAL1/2, IDLE1/2 Mode
TBTCR<DV7CK> = "0"
Serial Clock Baud Rate
12
3.906 kbps
fc/2
8
62.5 kbps
fc/2
7
125 kbps
fc/2
6
250 kbps
fc/2
5
500 kbps
fc/2
4
1.00 Mbps
fc/2
3
2.00 Mbps
fc/2
pin is kept in high level.
SCK1
Automatically wait
A4 A3 A2 A1 A0
Automatic wait is released by writing SIO1TDB
TBTCR<DV7CK> = "1"
Serial Clock Baud Rate
4
2048 bps
fs/2
8
62.5 kbps
fc/2
7
125 kbps
fc/2
6
250 kbps
fc/2
5
500 kbps
fc/2
4
1.00 Mbps
fc/2
3
2.00 Mbps
fc/2
Page 162
T5CL8
pin. At the before
SCK1
B7 B6 B5 B4 B3 B2 B1 B0
B
SLOW1/2, SLEEP1/2 Mode
Serial Clock Baud Rate
4
2048 bps
fs/2
Reserved –
Reserved –
Reserved –
Reserved –
Reserved –
Reserved