tmp88fw45afg TOSHIBA Semiconductor CORPORATION, tmp88fw45afg Datasheet - Page 216

• Manufacturer Part Number: tmp88fw45afg
• Description: 8 Bit Microcontroller Tlcs-870/x Series
• Manufacturer: TOSHIBA Semiconductor CORPORATION

17.3
Serial clock
17.3
17.3.1
17.3.1.1
17.3.1.2
Serial clock
Internal clock or external clock for the source clock is selected by SIOCR1<SCK>.
Clock source
SCK pin goes high when transfer starts.
cannot keep up with the serial clock rate, there is a wait function that automatically stops the serial clock and
holds the next shift operation until the read/write processing is completed.
should be set to input mode. To ensure shifting, a pulse width of more than 2
needed for the shift operation to execute certainly. Actually, there is necessary processing time for interrupting,
writing, and reading. The minimum pulse is determined by setting the mode and the program.
Any of six frequencies can be selected. The serial clock is output to the outside on the SCK pin. The
When data writing (in the transmit mode) or reading (in the receive mode or the transmit/receive mode)
An external clock connected to the SCK pin is used as the serial clock. In this case, the SCK (P43) port
Note:1 Kbit = 1024 bit (fc = 20 MHz)
SCK
pin (output)
SO
pin (output)
Written transmit
data
Internal clock
External clock
Figure 17-3 Automatic Wait Function (at 4-bit transmit mode)
Table 17-1 Serial Clock Rate
SCK
000
001
010
011
100
101
110
111
a
a
0
a
1
External
Clock
fc/2
fc/2
fc/2
fc/2
fc/2
fc/2
a
2
-
13
8
7
6
5
4
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NORMAL, IDLE mode
Automatically
wait function
a
3
b
156.25 Kbps
312.50 Kbps
625.00 Kbps
125.00 Kbps
78.13 Kbps
Baud Rate
2.44 Kbps
b
External
0
-
b
1
c
b
2
b
3
4
/fc is required. This pulse is
c
0
TMP88FW45AFG
c
1