87
CHAPTER 5. PERIPHERAL HARDWARE FUNCTIONS
(b) Serial bus interface control register (SBIC)
When the 3-wire serial I/O mode is used, SBIC is set as shown below (see 5.5.3 (2) “Serial bus interface
control register” for full details of SBIC).
SBIC is manipulated by bit manipulation instructions.
Reset input clears the SBIC register to 00H.
The shaded area indicates bits used in the 3-wire serial I/O mode.
Address 7 6 5 4 3 2 1 0 Symbol
FE2H BSYE ACKD ACKE ACKT CMDD RELD CMDT RELT SBIC
Bus Release Trigger Bit (W)
Command Trigger Bit (w)
Should not used in 3-wire serial I/O mode
Command trigger bit
CMDT The command signal (CMD) Trigger output control bit. The SO latch is cleared (0) by setting
this bit (CMDT = 1), after which the CMDT bit is automatically cleared (0).
Remarks (W) Write only
Bus release trigger bit (W)
RELT The command signal (REL) trigger output control bit. The SO latch is cleared (0) by setting
this bit (RELT = 1), after which the RELT bit is automatically cleared (0).
Note Bits other than RELT and CMDT should not be used in the 3-wire serial I/O mode.