Ethernet Controller Programming Model
MSC8113 Reference Manual, Rev. 0
Freescale Semiconductor
25-81
MRBLR0R1 specifies for the Ethernet controller how much space is available in each receive
buffer to which the RxBD is pointing.
Table 25-53. CRBPTR Bit Descriptions
Bit
Reset
Description
CRBPTR
0–28
0
Current Receive Buffer Descriptor Pointer
The value in this field increments by eight (bytes) or 32 (bytes), subject to ECNTRL[DBDS], each
time a descriptor is read from memory. In 32-byte mode (ECNTRL[DBDS] is set), this field must be
32-byte aligned so that bits 27 and 28 are reserved in 32-byte mode.
—
29–31
0
Reserved. Write to zero for future compatibility.
MRBLR0R1
Maximum Receive Buffer Length R0R1 Register
Bit
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
MRBLR1
—
Type
R/W
R
Reset
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Bit
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
MRBLR0
—
Type
R/W
R
Reset
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Table 25-54. MRBLR0R1 Field Descriptions
Bit
Reset
Description
MRBLR1
10–9
0
Maximum Receive Buffer Length for Ring 1
Specifies the number of bytes that the Ethernet controller receiver writes to receive buffer ring 1
before moving to the next buffer. You write to MRBLR1 with a multiple of 64 for all modes. The
Ethernet controller can write fewer bytes to the buffer than the value set in MRBLR1 if a condition
such as an error or end-of-frame occurs, but it never exceeds the MRBLR1 value. Therefore,
user-supplied buffers must be at least as large as MRBLR1. Note that you can assign transmit
buffers varying lengths by programming TxBD[DL] as needed, and they are not affected by the
value in MRBLRn. MRBLRn is not to be changed dynamically while the Ethernet controller is
operating. Change MRBLRn only when the Ethernet controller receive function is disabled.
—
10–15
0
To ensure that MRBL1 and MRBLR0 are multiples of 64, these bits are reserved and must be
cleared.
MRBLR0
16–25
0
Maximum Receive Buffer Length for Ring 0
Specifies the number of bytes that the Ethernet controller receiver writes to receive buffer ring 0
before moving to the next buffer. You write to MRBLR0 register with a multiple of 64 for all modes.
The Ethernet controller can write fewer bytes to the buffer than the value set in MRBLR0 if a
condition such as an error or end-of-frame occurs, but it never exceeds the MRBLR0 value.
Therefore, user-supplied buffers must be at least as large as the MRBLR0.
—
26–31
0
To ensure that MRBLR1 and MRBLR0 are multiples of 64, these bits are reserved and should be
cleared.
Summary of Contents for MSC8113
Page 1: ...MSC8113 Reference Manual Tri Core 16 Bit Digital Signal Processor MSC8113RM Rev 0 May 2008 ...
Page 20: ...MSC8113 Reference Manual Rev 0 xx Freescale Semiconductor Contents ...
Page 28: ...MSC8113 Reference Manual Rev 0 xxviii Freescale Semiconductor ...
Page 56: ...MSC8113 Reference Manual Rev 0 1 28 Freescale Semiconductor MSC8113 Overview ...
Page 76: ...MSC8113 Reference Manual Rev 0 2 20 Freescale Semiconductor SC140 Core Overview ...
Page 134: ...MSC8113 Reference Manual Rev 0 4 30 Freescale Semiconductor System Interface Unit SIU ...
Page 168: ...MSC8113 Reference Manual Rev 0 6 18 Freescale Semiconductor Boot Program ...
Page 180: ...MSC8113 Reference Manual Rev 0 7 12 Freescale Semiconductor Clocks ...
Page 260: ...MSC8113 Reference Manual Rev 0 8 80 Freescale Semiconductor Memory Map ...
Page 300: ...MSC8113 Reference Manual Rev 0 9 40 Freescale Semiconductor Extended Core ...
Page 304: ...MSC8113 Reference Manual Rev 0 10 4 Freescale Semiconductor MQBus and M2 Memory ...
Page 308: ...MSC8113 Reference Manual Rev 0 11 4 Freescale Semiconductor SQBus ...
Page 590: ...MSC8113 Reference Manual Rev 0 17 46 Freescale Semiconductor Interrupt Processing ...
Page 614: ...MSC8113 Reference Manual Rev 0 18 24 Freescale Semiconductor Debugging ...
Page 622: ...MSC8113 Reference Manual Rev 0 19 8 Freescale Semiconductor Internal Peripheral Bus IPBus ...
Page 724: ...MSC8113 Reference Manual Rev 0 21 32 Freescale Semiconductor UART ...
Page 920: ...MSC8113 Reference Manual Rev 0 25 150 Freescale Semiconductor Ethernet Controller ...
Page 1171: ...MSC8113 Reference Manual Rev 0 Freescale Semiconductor C 61 EF wait_rts P 01077FFC 9F rts 71 ...
Page 1172: ...MSC8113 Reference Manual Rev 0 C 62 Freescale Semiconductor MSC8113 Boot Code ...
Page 1202: ...MSC8113 Reference Manual Rev 0 Index 30 Freescale Semiconductor Index ...