LAN83C175 Datasheet, PDF (50/92 Pages) SMSC Corporation – Ethernet CARDBUS Integrated Controller With Modem Support

78 - TRANSMIT PACKET ADDRESS
Reset Value: 000000000
This register contains the transmit MTU’s
pointer to the starting address of the current
frame in the local transmit ram. The register
contains the dword address and is write only.
Reads to this register return unknown data.
31 through 9 - Unused.
8 through 0 - Address.
7C - TRANSMIT TEST
31 through 12 - Unused.
11 through 8 - Reserved: Do not write ‘1’ to
these bits.
7 - Force collision.
6 through 0 - Reserved: Do not write ‘1’ to
these bits.
80 - CardBus RECEIVE FIRST DESCRIPTOR
ADDRESS
Reset Value:
xxxxxxxxxxxxxxxxxxxxxxxxxxxxxx00
This register contains the byte address of the
first descriptor for the current receive packet.
It is the location in host memory where the
receive status will be posted when receive
copy is complete. The two lsb’s are fixed at
zero so the address will always be dword
aligned. This register is automatically written
with the same data as the PRCDAR register
whenever a write to that register occurs.
31 through 2 - CardBus Address.
1 through 0 - Not writable - always return zeroes.
84 - CardBus RECEIVE CURRENT
DESCRIPTOR ADDRESS
Reset Value:
XXXXXXXXXXXXXXXXXXXXXXXXXXXXXX 00
This register contains the byte address (in host
memory) of the next descriptor that the receive
DMA will read. The two lsb's are fixed at zero so
the address will always be dword aligned. This
register must be initialized once after reset.
31 through 2 - CardBus ADDRESS
1 and 0 - Not writable - always return zeroes.
88 - CardBus RECEIVE HOST DATA ADDRESS
Reset Value: xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
This register contains the address where receive
packet data is to be written in host memory. The
upper 30 bits are driven onto the CardBus bus as
the dword address, and are incremented each
time a dword is written to host memory. The two
lsb’s always contain the starting byte address of
the data buffer, and are used by the receive DMA
to control byte alignment.
31 through 2 - CardBus Address.
1 and 0 - Starting Byte Address.
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