NEC PD78214 - Manual (Page 292)

263
Chapter 10 Clock Synchronous Serial Interface
10
10.3.2 Serial Bus Interface Control Register (SBIC)
The SBIC register consists of bits that control the status of the serial bus, as well as bits that indicate the status
of the data input from the serial bus. This 8-bit register can be used only in SBI mode, not in three-wire serial
I/O mode.
The 8-bit manipulation instruction and bit manipulation instruction manipulate the contents of the register. These
bits have different read/write attributes, listed in Table 10-1. When the contents are read, 0 is read from the write-
only bits. The format is shown in Fig. 10-3.
The register is set to 00H when RESET is input.
Detection flags ACKD, CMDD, and RELD are cleared when transmission and reception are inhibited (both CTXE
and CRXE are set to 0).
Table 10-1 Reading/Writing the Contents of the SBIC Register
BSYE
R/W
ACKD
R
ACKE
R/W
ACKT
W
CMDD
R
RELD
R
CMDT
W
RELT
W
5 4 3 7 6 2 1 0
SBIC
Remarks R/W : Read/write
R : Read-only
W : Write-only