BCM1250/BCM1125/BCM1125H
User Manual
10/21/02
B r o a d c o m C o r p o r a t i o n
Page
174
Section 7: DMA
Document
1250_1125-UM100CB-R
C
ONTROL
AND
F
LAG
B
ITS
FOR
S
YNCHRONOUS
S
ERIAL
I
NTERFACE
Table 108: Status Flags for Synchronous Serial Receive Channel
Receive Status Flags
Bits
Name
Description
55:51 reserved
Reserved
56
crc_error
This bit is set if the received packet has a bad CRC.
57
abort
This bit is set if the received packet ended with the abort flag.
58
octet_error
This bit is set if the size of the received packet was not a multiple of 8 bits.
59
longframe_error
This bit is set if the size of the received packet is bigger than the maximum frame size.
60
shortframe_error This bit is set if the size of the received packet is shorter than the minimum frame size.
61
overun_error
This bit is set if the received packet over ran the FIFO and is therefore invalid.
62
good
This bit is set if the received packet has no errors.
63
SOP
This bit is set to indicate the start of the packet. Software should ensure this bit is clear when
it sets up the descriptor, the DMA controller will only set it when packet reception has been
completed.
Table 109: Option Flags for Synchronous Serial Receive Channel
Receive Options
Bits
Name
Description
None
Table 110: Status Flags for Synchronous Serial Transmit Channel
Transmit Status Flags
Bits
Name
Description
62:51
ignored
Preserved when the descriptor is written.
63
Flag
This bit is cleared when the descriptor is written. Software can set this bit in descriptors associated
with the start of a packet and the bit will be cleared when the packet has been transmitted. (Unlike
the Ethernet there is no requirement that this bit be set for a SOP).
Table 111: Option Flags for Synchronous Serial Transmit Channel
Transmit Commands
Bits
Name
Description
0 reserved
Reserved
1
append CRC If this bit is set the computed CRC will be appended to the packet.
2
append PAD If this bit is set the packet will be padded to the minimum packet size.
3
abort
If this bit is set the packet will be ended with an abort instead of a standard flag.
Содержание BCM1125
Страница 18: ...BCM1250 BCM1125 BCM1125H User Manual 10 21 02 Broadcom Corporation Page xviii Document 1250_1125 UM100CB R ...
Страница 28: ...BCM1250 BCM1125 BCM1125H User Manual 10 21 02 Broadcom Corporation Page xxviii Document 1250_1125 UM100CB R ...
Страница 515: ...BCM1250 BCM1125 BCM1125H User Manual 10 21 02 Broadcom Corporation Page vii Index Document 1250_1125 UM100CB R ...