CHAPTER 15 CLOCKED SERIAL INTERFACE 0 (CSI0)
User’s Manual U16896EJ2V0UD
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(5) Clocked serial interface transmit buffer registers n, nL (SOTBn, SOTBnL)
The SOTBn register is a 16-bit buffer register that stores transmit data.
When the transmission/reception mode is set (CSIM0n.TRMDn bit = 1), the transmission operation is started
by writing data to the SOTBn register.
This register can be read or written in 16-bit units. However, when the lower 8 bits are used as the SOTBnL
register, the register can be read or written in 8-bit units.
Reset sets this register to 0000H.
Cautions 1. Access the SOTBn register only when a 16-bit data length has been set (CSIM0n.CCLn
bit = 1).
Access the SOTBnL register only when an 8-bit data length has been set (CCLn bit = 0).
2. When the single transfer mode is set (CSIM0n.AUTOn bit = 0), perform access only in
the idle state (CSIM0n.CSOTn bit = 0). If the SOTBn and SOTBnL registers are accessed
during data transfer, the data cannot be guaranteed.
(a) SOTBn register
14
SOTBn
14
13
SOTBn
13
12
SOTBn
12
2
SOTBn
2
3
SOTBn
3
4
SOTBn
4
5
SOTBn
5
6
SOTBn
6
7
SOTBn
7
8
SOTBn
8
9
SOTBn
9
10
SOTBn
10
11
SOTBn
11
15
SOTBn
15
1
SOTBn
1
0
SOTBn
0
SOTBn
(n = 0, 1)
After reset: 0000H R/W Address: SOTB0 FFFFFD04H, SOTB1 FFFFFD14H
(b) SOTBnL register
7
SOTBn7
SOTBnL
(n = 0, 1)
6
SOTBn6
5
SOTBn5
4
SOTBn4
3
SOTBn3
2
SOTBn2
1
SOTBn1
0
SOTBn0
After reset: 00H R/W Address: SOTB0L FFFFFD04H, SOTB1L FFFFFD14H