Fujitsu F2MC-8L F202RA Hardware Manual page 297

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Serial Switch
UART and 8-bit serial I/O use the same pins, thus they cannot be simultaneously used. The serial switch
circuit needs be used to select either of them.
When UART is selected using the serial switch, P30/UCK/SCK is used as the UART serial clock I/O pin
(UCK), P31/UO/SO is used as the UART data output pin (UO), and P32/UI/SI is used as the UART data
input pin (UI).
Note:
In this chapter, the pin function switch and register functions are explained on the presupposition that
UART is selected using the serial switch circuit.
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Choice of the Transfer Clock Rate
Figure 13.1-1 Baud Rate Generator and Serial Clock Generator
PR2 to PR0
1/2
1/3
t /2
INST
1/4
1/5
PWM
output
UCK
t : Instruction cycle
INST
● Example of the baud rates selectable when the dedicated baud rate generator is used
Table 13.1-2 lists the baud rates selectable when the dedicated baud rate generator is used.
Table 13.1-2 Transfer Cycles and Transfer Rates Available for the Dedicated Baud Rate Generator
(when F
CH
RC2 RC1 RC0
0 0 0
0 0 1
0 1 0
0 1 1
1 0 0
1 0 1
1 1 0
1 1 1
RC2 to RC0
UART prescaler
1/2 1
(1/2) n
1/4 1/13
When RC2 and RC1
= 1, the divider is 1
even in asynchronous
mode.
= 12.5 MHz)
Divider for baud rate
(multiplier = n)
1(0)
2(1)
4(2)
8(3)
16(4)
32(5)
2(1)
16(4)
CS1, CS0
1
1/2
Transfer rate (µs/baud)
Clock divider = 2.5
(PR2=0, PR1=1, PR0=0)
Asynchronous Synchronous
transfer transfer
83/12019 0.8/1.25M
166/6010 1.6/625k
333/3005 3.2/313k
666/1503 6.4/156k
1331/751 12.8/78k
2662/375 25.6/39k
13/78125 1.6/625k
102/9766 12.8/78k
CHAPTER 13 UART
SMDE
CR
1/8
1/16
1/64
Clock divider = 1
(PR2=0, PR1=0, PR0=0)
Asynchronous
transfer
33/30048
67/15024
133/7512
266/3756
532/1878
1065/939
5.12/195k
41/24k
Serial
clock
Synchronous
transfer
0.32/3.1M
0.64/1.6M
1.28/781k
2.56/391k
5.12/195k
10.24/98k
0.64/1.6M
5.12/195k
281