M16C29 Datasheet, PDF (242/499 Pages) Renesas Technology Corp – RENESAS MCU M16C FAMILY / M16C/Tiny SERIES

M16C/29 Group
14. Serial I/O
SI/Oi Control Register (i = 3, 4) ⁽¹⁾
b7 b6 b5 b4 b3 b2 b1 b0
Symbol
S3C
S4C
Address
036216
036616
After Reset
010000002
010000002
Bit
Symbol
Bit Name
Function
RW
SMi0 Internal synchronous clock ^{b1 b0}
select bit ⁽⁵⁾
0 0 : Selecting f1 or f2
RW
0 1 : Selecting f8
SMi1
1 0 : Selecting f32
1 1 : Do not set
RW
SMi2 SOUTi output disable bit ⁽⁴⁾ 0 : SOUTi output
1 : SOUTi output disable(high impedance)
RW
SMi3 S I/Oi port select bit
0 : Input/output port
1 : SOUTi output, CLKi function
RW
SMi4
SMi5
CLK polarity selct bit
Transfer direction select bit
0 : Transmit data is output at falling edge of
transfer clock and receive data is input at
rising edge
RW
1 : Transmit data is output at rising edge of
transfer clock and receive data is input at
falling edge
0 : LSB first
1 : MSB first
RW
SMi6
Synchronous clock select bit 0 : External clock (2)
1 : Internal clock ⁽³⁾
RW
SMi7 SOUTi initial value set bit
Effective when the SMi3 is set to 0
0 : “L” output
1 : “H” output
RW
NOTES:
1. Set the S4C register by the next instruction after setting the PRC2 bit in the PRCR register to 1 (write enable).
2. Set the SMi3 bit to 1 and the corresponding port direction bit to 0 (input mode).
3. Set the SMi3 bit to 1 (SOUTi output, CLKi function) .
4. When the SMi2 bit is set to 1, the corresponding pin goes to high-impedance regardless of the function in use.
5. When the SMi1 and SMi0 bit settings are changed, set the SiBRG register .
SI/Oi Bit Rate Generation Register (i = 3, 4) ^{(1, 2, 3)}
b7
b0
Symbol
Address
S3BRG
036316
S4BRG
036716
After Reset
Undefined
Undefined
Description
Assuming that set value = n, BRGi divides the count source by
n+1
NOTES:
1. Write to this register while serial I/O is neither transmitting or receiving.
2. Use MOV instruction to write to this register.
3. Set the SiBRG register after setting bits SMi1 and SMi0 in the SiC register.
Setting Range
0016 to FF16
RW
WO
SI/Oi Transmit/Receive Register (i = 3, 4) ^{(1, 2)}
b7
b0
Symbol
Address
S3TRR
036016
S4TRR
036416
After Reset
Undefined
Undefined
Description
RW
Transmission/reception starts by writing transmit data to this register. After
RW
transmission/reception completion, reception data can be read by reading this register.
NOTES:
1. Write to this register while serial I/O is neither transmitting or receiving.
2. To receive data, set the corresponding port direction bit for SINi to 0 (input mode).
Figure 14.36 S3C and S4C Registers, S3BRG and S4BRG Registers, and S3TRR and S4TRR Registers
Rev. 1.12 Mar.30, 2007 ^{page 218} of 458
REJ09B0101-0112