IBM PowerPC 405GP User Manual page 633

4
. . . . . \n'··
Reserved
5:7 MTC Master Transfer Count
000 0 bytes transferred
001 1 byte transferred
010 2 bytes transferred
011 3 bytes transferred
100 4 bytes transferred
101 Reserved
110 Reserved
111 Reserved
IICO_XFRCNT[MTC] is cleared when there is a pending transfer, IICO_CNTL[PT] = 1.
IICO_XFRCNT[STC] is cleared when:
• ,A
slave operation starts on the IIC bus
• Software indicates the slave does not need service by clearing IICO_XTCNTLSS[SRS] or
IICO_XTCNTLSS[SWS].
22.3.14 IICO Extended Control and Slave Status Register
The IICO Extended Control and Slave Status Register (IICO_XTCNTLSS) provides additional control
of IIC interface functions and reports the status of slave operations.
Figure 22-17 illustrates the IICO_XTCNTLSS.
0
22-18
SRC SWC SBDD
EPI
~ ~ ~ ~
10111213141516171
t t t t
SRS SWS SDBF SRST
Figure 22-17.
IICO
Extended Control and Slave Status Register (IICO_XTCNTLSS)
SRC Slave Read Complete Check whether the read operation emptied
o
Normal operation, or
IICO_SDBUF.
IICO_MDCNTL[HSCL]
=
0, IICO_SDBUF
is empty, and a read operation is in
progress.
1 A NACK or Stop condition was received
over the IIC bus, or a repeated Start
condition ended a read operation.
PPC405GP User's Manual Preliminary