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GR716-DS-UM, May 2019, Version 1.29
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GR716
33.11.8
Table 408.
0x24 - DMAMAXLEN - DMA RX maximum length
DMA RX Maximum Length
33.11.9
Table 409.
0x28 - DMATXDESC - DMA transmit descriptor table address
DMA Transmit Descriptor Table Address
33.11.10
Table 410.
0x2C - DMARXDESC - DMA receive descriptor table address
DMA Receive Descriptor Table Address
31
25 24
2
1
0
RESERVED
RXMAXLEN
RES
0x00
n/r
0x0
r
rw
r
31: 25
RESERVED
24: 2
RX maximum length (RXMAXLEN) - Receiver packet maximum length, counted in 32-bit words.
1: 0
RESERVED
31
x+1 x
4
3
0
DESCBASEADDR
DESCSEL
RESERVED
n/r
0x00
0x0
rw
rw
r
31: x+1
Descriptor table base address (DESCBASEADDR) - Sets the base address of the descriptor table.
The number of bits in this field depends on the size of the DMA transmit descriptor table. The value
of x is given by the formula: 9 + STS.NTXD.
x: 4
Descriptor selector (DESCSEL) - Offset into the descriptor table. Shows which descriptor is cur-
rently used by the core. For each new descriptor read, the selector will increase with 16 and eventu-
ally wrap to zero again. The number of bits in this field depends on the size of the DMA transmit
descriptor table. The value of x is given by the formula: 9 + STS.NTXD.
3: 0
RESERVED
31
x+1 x
3
2
0
DESCBASEADDR
DESCSEL
RESERVED
n/r
0x00
0x0
rw
rw
r
31: 10
Descriptor table base address (DESCBASEADDR) - Sets the base address of the descriptor table.
The number of bits in this field depends on the size of the DMA receive descriptor table. The value
of x is given by the formula: 9 + STS.NRXD.
9: 3
Descriptor selector (DESCSEL) - Offset into the descriptor table. Shows which descriptor is cur-
rently used by the core. For each new descriptor read, the selector will increase with 8 and eventually
wrap to zero again. The number of bits in this field depends on the size of the DMA receive descrip-
tor table. The value of x is given by the formula: 9 + STS.NRXD
2: 0
RESERVED