
R8C/3GM Group
24. Synchronous Serial Communication Unit (SSU)
R01UH0284EJ0100 Rev.1.00
Aug 09, 2011
24.2.5
SS Receive Data Register (SSRDR)
Notes:
1. The SSRDR register retains the data received before an overrun error occurs (ORER bit in the SSSR register set
to 1 (overrun error)). When an overrun error occurs, the receive data may contain errors and therefore should be
discarded.
2. When the SSU data transfer length is set to 9 bits or more with the SSBR register, access the SSRDR register in
16-bit units.
24.2.6
SS Control Register H (SSCRH)
Notes:
1. The set clock is used when the MSS bit is set to 1 (operates as master device).
2. The SSCK pin functions as the transfer clock output pin when the MSS bit is set to 1 (operates as master
device). The MSS bit is set to 0 (operates as slave device) when the CE bit in the SSSR register is set to 1
(conflict error occurs).
3. The RSSTP bit is disabled when the MSS bit is set to 0 (operates as slave device).
Address 0197h to 0196h
Bit
b7b6b5
b4b3b2
b1b0
Symbol
After Reset
111
11
Bit
b15
b14
b13
b12
b11
b10
b9
b8
Symbol
After Reset
111
11
Bit
Symbol
Function
R/W
b15 to b0
—
Store the receive data.
(1, 2)The receive data is transferred to the SSRDR register and the receive operation is
completed when 1 byte of data has been received by the SSTRSR register. At this time,
the next receive operation is possible.
Continuous reception is possible using registers SSTRSR and SSRDR.
R
Address 0198h
Bit
b7b6b5
b4b3b2
b1b0
Symbol
After Reset
000
00
Bit
Symbol
Bit Name
Function
R/W
b0
CKS0
Transfer clock select bit
(1)b2 b1 b0
0 0 0: f1/256
0 0 1: f1/128
0 1 0: f1/64
0 1 1: f1/32
1 0 0: f1/16
1 0 1: f1/8
1 1 0: f1/4
1 1 1: Do not set.
R/W
b1
CKS1
R/W
b2
CKS2
R/W
b3
—
Nothing is assigned. If necessary, set to 0. When read, the content is 0.
—
b4
—
b5
MSS
Master/slave device select bit
(2)0: Operates as slave device
1: Operates as master device
R/W
b6
RSSTP Receive single stop bit
(3)0: Maintains receive operation after receiving 1 byte of
data
1: Completes receive operation after receiving 1 byte
of data
R/W
b7
—
Nothing is assigned. If necessary, set to 0. When read, the content is 0.
—