Samsung S3C2500B User Manual page 333

S3C2500B
7.4.1.11 BDMA Receive Frame Size Register
Registers Address
BDMARXLENA 0xF00A0028
BDMARXLENB 0xF00C0028
Bit Number
[11:0] BDMA Rx Buffer Size
(BRxBS)
[15:12] Reserved
[27:16] BDMA Maximum Rx Frame
Size (BRxMFS)
[31:28] Reserved
Table 7-24. BDMARXLEN Register
R/W
R/W
R/W
Table 7-25. BDMA Receive Frame Size Register Description
Bit Name
This register value specifies the buffer size allocated to each
buffer descriptor. Thus, for an incoming frame larger than the
BRxBS, multiple buffer descriptors are used for the frame
reception.
NOTE: BRxBS value has to keep multiples of 16 in byte unit.
Not applicable
This register value controls how many bytes per frame can be
saved to memory. If the received frame size exceeds these
values, an error condition is reported.
NOTE: BRxMFS value has to keep multiples of 16 in byte unit.
Not applicable
Description
Receive frame size
Receive frame size
Description
For long packet reception larger than 1518 bytes, the BRxBS
should be at least 4 bytes larger than the BRxMFS or less
than 1518 bytes for the reception with a single or multiple
buffer descriptor, respectively.
ETHERNET CONTROLLER
Reset Value
Undefined
Undefined
7-23