CHAPTER 13 SERIAL INTERFACE CHANNEL 0
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User’s Manual U11302EJ4V0UM
(b) Serial bus interface control register (SBIC)
SBIC is set with a 1-bit or 8-bit memory manipulation instruction.
RESET input sets SBIC to 00H.
R/W
RELT
Used for bus release signal output.
When RELT = 1, the SO latch is set to 1. After SO latch setting, RELT is automatically cleared to 0.
Also cleared to 0 when CSIE0 = 0.
R/W
CMDT
Used for command signal output.
When CMDT = 1, the SO latch is cleared to 0. After SO latch clearance, CMDT is automatically cleared to 0.
Also cleared to 0 when CSIE0 = 0.
R
RELD
Bus release detection
Clear conditions (RELD = 0)
Set conditions (RELD = 1)
• When transfer start instruction is executed
• When bus release signal (REL) is detected
• If SIO0 and SVA values do not match in address
reception
• When CSIE0 = 0
• When RESET input is applied
R
CMDD
Command detection
Clear conditions (CMDD = 0)
Set conditions (CMDD = 1)
• When transfer start instruction is executed
• When command signal (CMD) is detected
• When bus release signal (REL) is detected
• When CSIE0 = 0
• When RESET input is applied
R/W
ACKT
The acknowledge signal is output in synchronization with the falling edge clock of SCK0 just after
execution of the instruction to be set to 1, and after acknowledge signal output, ACKT is
automatically cleared to 0.
Used as ACKE = 0. Also cleared to 0 upon start of serial interface transfer or when CSIE0 = 0.
(continued)
Note
Bits 2, 3, and 6 (RELD, CMDD, and ACKD) are read-only bits.
Remarks
1.
Bits 0, 1, and 4 (RELT, CMDT, and ACKT) are 0 when read after data setting.
2.
CSIE0: Bit 7 of serial operating mode register 0 (CSIM0)
<6>
<5>
<4>
<3>
<2>
<1>
<0>
<7>
Symbol
SBIC
BSYE ACKD ACKE ACKT CMDD RELD CMDT RELT
FF61H 00H R/W
Note
Address After reset R/W