
6.0 ACCESS.bus Interface
(Continued)
Revision 1.2
127
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P
6.3.2
This register controls the ACCESS.bus interface and holds the status of the last transactions. On reset, it is cleared (01h).
Power Well:V
SB
Location:
Offset 00h
Type:
Varies per bit
ACCESS.bus Control/Status Register (ACBCST)
Bit
7
6
5
4
3
2
1
0
Name
OFFLDN
ILGCOM
PECERR
BUSERR
LOWCKTO
ACCLVIOL
VDDSTAT
PECAVAIL
Reset
0
0
0
0
0
0
0
1
Bit
Type
Description
7
R/W1C
OFFLDN (Accessed LDN Powered-off Flag).
Indicates that the Logical Device accessed through the
command byte (only for Internal Access mode, i.e., when INEX = 0) is powered-off (relevant for the
Legacy functional blocks powered from the V
DD
plane). Writing ‘1’ clears this bit; writing ‘0’ is ignored.
0: Powered Logical Device accessed (default)
1: Unpowered Logical Device accessed
6
R/W1C
ILGCOM (Illegal Command Flag).
Indicates that an illegal command code or an incorrect number of
address/data bytes was received or requested for transmission (by last byte NACK or Stop control).
Writing ‘1’ clears this bit; writing ‘0’ is ignored.
0: Correct protocol (default)
1: Illegal command or number of bytes
5
R/W1C
PECERR (PEC Error Flag).
Indicates that a PEC error was detected in the write transaction bytes that
were received from the master. This bit is not updated if the master does not send a PEC byte. Writing
‘1’ clears this bit; writing ‘0’ is ignored.
0: Correct PEC (default)
1: CRC of the received bytes differs from the received PEC
4
R/W1C
BUSERR (Bus Error Flag).
Indicates that an unexpected Start, Restart or Stop Condition was detected
during a read or write transaction. Writing ‘1’ clears this bit; writing ‘0’ is ignored.
0: Correct transaction (default)
1: Illegal Start, Restart or Stop Condition
3
R/W1C
LOWCKTO (Low Clock Timeout Flag).
Indicates that the ACBCLK signal was detected low for longer
than the maximum allowed “cumulative clock low extend time” during a transaction, as defined in
Section 11.5.6 on page 246. Writing ‘1’ clears this bit; writing ‘0’ is ignored.
0: Correct clock low timing (default)
1: Clock low timeout
2
R/W1C
ACCLVIOL (Access Lock Violation Flag).
Indicates that an LPC access to a functional module locked
for sole use by ACCESS.bus was detected. Writing ‘1’ clears this bit; writing ‘0’ is ignored.
0: Correct LPC access (default)
1: LPC access to a locked functional module
1
RO
VDDSTAT (V
DD
Power Status).
Indicates the actual status of the V
DD
power supply to the PC8741x
device.
0: V
DD
power Off
1: V
DD
power On
0
RO
PECAVAIL (PEC Feature Available).
Enables the master to detect the availability of the PEC
implementation in the slave.
0: Peripheral does not support PEC
1: Peripheral supports PEC (default and fixed value for PC8741x devices)