![](http://datasheet.mmic.net.cn/390000/TSB42AA4I_datasheet_16839080/TSB42AA4I_156.png)
659
0x244 TXDPSTAT – Transmit Data Path Status
BIT
NAME
TYPE
RESET
FUNCTION
31:30
RSVD
R0
0
Reserved – A write to this location has no effect. A read returns 0s.
29
VIDSEL_ERR
RU
0
Video select error – This bit is set by hardware if a buffer is selected for
video A and video B at the same time or more than two total video paths
are selected.
28
ACKC_ERR
RU
0
Acknowledge code error – When this bit is set to 1, an acknowledge code
was returned with an error. This indicates that the asynchronous packet
has experienced a transmit failure.
27:24
ACKCODE
RU
0
Acknowledge code – the value in this field represents the 1394 ACK code
generated by the receiving node. ACK complete is always returned by the
link layer controller internally for asynchronous streaming and broadcast
packets. A list of ACK codes is included in Table 510.
23:22
RSVD
R0
0
Reserved – A write to this location has no effect. A read returns 0s.
21:16
NODEID
RU
0
Destination node ID – Not valid for asynchronous streaming data.
15:8
PKTID
RU
0
Packet identifier – This field encodes the packet identification information
for the current transmit packet. This field represents bits 8 through 20 of
the first quadlet of the transmitted 1394 packet, respectively.
7:4
TCODE
R0
0
IEEE-1394 TCODE – This field represents the TCODE of the transmitted
packet.
3
RSVD
R0
0
Reserved A write to this location has no effect. A read returns 0.
2:0
ACKCNT
R
0
ACK count – This binary encoded value represents the number of ACKS
currently available within the ACK FIFO.
0x248 TXDPINT – Transmit Data Path Interrupts
BIT
NAME
TYPE
RESET
FUNCTION
31:28
RSVD
R0
0
Reserved – A write to this location has no effect. A read returns 0s.
27
ERRASYTX
RCU
0
Asynchronous transmit error – This bit is set by hardware when the
number of retries (defined in the TxDPCTL.ATRETRYMAX field) has
expired, an error acknowledge code was returned, or an illegal tCode was
written into the asynchronous header register.
26
ACKLOST
RCU
0
Acknowledge lost – This bit is set by hardware when the ACK buffer has
an overrun condition.
25
ACKRCVD
RCU
0
Acknowledge received – When this bit is set to 1 by hardware, an ACK
has been written to the ACK FIFO by the TXDP. When this bit is set and
the TXDPINTEN.ACKRCVD bit is set, an interrupt is generated.
24
ERRISOTX
RCU
0
Isochronous transmit error – When this bit is set to 1 by hardware, the
TXDP has detected an error in an attempted isochronous transmission.
The error was caused by an illegal tCode or by the fact that the data length
of the actual packet does not equal the data length field in the isochronous
header.
23
ERRBFLSH0
RCU
0
Buffer 0 flushed due to an error – When this bit is set to 1 by hardware, the
TXDP has flushed the transmit buffer due to an error. This only occurs
when TXDP(N)CFG.BUFFLSHEN is set to 1.