CS8900-CQ3 Cirrus Logic, CS8900-CQ3 Datasheet - Page 57

• Manufacturer Part Number: CS8900-CQ3
• Description: Crystal LAN ISA Ethernet Controller
• Manufacturer: Cirrus Logic

DS271PP3
4.4.10 Register 8: Transmitter Event
(TxEvent, Read-only, Address: PacketPage base + 0218h)
TxEvent gives the event status of the last packet transmitted.
001000
Loss-of-CRS
SQEerror
TxOK
Out-of-Window
Jabber
#-of-TX-collisions
16coll
Reset value is:
Notes:
CS8900A
Crystal LAN™ ISA Ethernet Controller
SQEerror
16coll
F
7
1.In any event register, like TxEvent, all bits are cleared upon readout. The host is responsible for
processing all event bits.
2.TxOK (Bit 8) and the Number-of-Tx-Collisions (Bits E-B) are used in normal packet transmission.All
other bits (6, 7, 9, A, and F) give the status of abnormal transmit operation.
Loss-of-CRS
0000 0000 0000 1000
Event Register.
the preamble, there is a Loss-of-Carrier error and this bit is set. If Loss-of-CRSiE (Register 7,
TxCFG, Bit 6) is set, there is an interrupt.
times. If this does not happen, there is an SQE error and this bit is set. If SQEerroriE (Register
7, TxCFG, Bit 7) is set, there is an interrupt.
sion (Bit 9), and 16Coll (Bit F) must all be clear). If TxOKiE (Register 7, TxCFG, Bit 8) is set,
there is an interrupt.
this occurs, the CS8900A forces a bad CRC and terminates the transmission. If Out-of-window-
iE (Register 7, TxCFG, Bit 9) is set, there is an interrupt
ber logic and this bit is set. If JabberiE (Register 7, TxCFG, Bit A) is set, there is an interrupt.
Bit B is the LSB. If AnycolliE (Register 7, TxCFG, Bit B) is set, there is an interrupt when any
collision occurs.
particular packet. When this happens, the CS8900A stops further attempts to send that packet.
If 16colliE (Register 7, TxCFG, Bit F) is set, there is an interrupt.
These bits provide an internal address used by the CS8900A to identify this as the Transmitter
If the CS8900A is transmitting on the AUI and doesn’t see Carrier Sense (CRS) at the end of
At the end of a transmission on the AUI, the CS8900A expects to see a collision within 64 bit
This bit is set if the last packet was completely transmitted (Jabber (Bit A), out-of-window-colli-
This bit is set if a collision occurs more than 512 bit times after the first bit of the preamble. When
If the last transmission is longer than 26 msec, then the packet output is terminated by the jab-
These bits give the number of transmit collisions that occurred on the last transmitted packet.
This bit is set if the CS8900A encounters 16 normal collisions while attempting to transmit a
E
6
Number-of-Tx-collisions
D
5
CIRRUS LOGIC PRODUCT DATA SHEET
C
4
B
3
001000
Jabber
A
2
Out-of-window
1
9
TxOK
0
8
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