Filter
Top Products
www.ti.com
5.23ReceiveMaximumLengthRegister(RXMAXLEN)
5.24ReceiveBufferOffsetRegister(RXBUFFEROFFSET)
EthernetMediaAccessController(EMAC)Registers
Thereceivemaximumlengthregister(RXMAXLEN)isshowninFigure49anddescribedinTable48.
Figure49.ReceiveMaximumLengthRegister(RXMAXLEN)
3116
Reserved
R-0
150
RXMAXLEN
R/W-5EEh
LEGEND:R=Readonly;R/W=Read/Write;-n=valueafterreset
Table48.ReceiveMaximumLengthRegister(RXMAXLEN)FieldDescriptions
BitFieldValueDescription
31-16Reserved0Reserved
15-0RXMAXLEN0-FFFFhReceivemaximumframelength.Thesebitsdeterminethemaximumlengthofareceivedframe.
Theresetvalueis5EEh(1518).FrameswithbytecountsgreaterthanRXMAXLENarelong
frames.Longframeswithnoerrorsareoversizedframes.LongframeswithCRC,code,or
alignmenterrorarejabberframes.
Thereceivebufferoffsetregister(RXBUFFEROFFSET)isshowninFigure50anddescribedin
Table49.
Figure50.ReceiveBufferOffsetRegister(RXBUFFEROFFSET)
3116
Reserved
R-0
150
RXBUFFEROFFSET
R/W-0
LEGEND:R=Readonly;R/W=Read/Write;-n=valueafterreset
Table49.ReceiveBufferOffsetRegister(RXBUFFEROFFSET)FieldDescriptions
BitFieldValueDescription
31-16Reserved0Reserved
15-0RXBUFFEROFFSET0-FFFFhReceivebufferoffsetvalue.ThesebitsarewrittenbytheEMACintoeachframeSOP
bufferdescriptorBufferOffsetfield.TheframedatabeginsaftertheRXBUFFEROFFSET
valueofbytes.Avalueof0indicatesthattherearenounusedbytesatthebeginningof
thedata,andthatvaliddatabeginsonthefirstbyteofthebuffer.AvalueofFh(15)
indicatesthatthefirst15bytesofthebufferaretobeignoredbytheEMACandthatvalid
bufferdatastartsonbyte16ofthebuffer.Thisvalueisusedforallchannels.
SPRU941A–April2007EthernetMediaAccessController(EMAC)/91
ManagementDataInput/Output(MDIO)
SubmitDocumentationFeedback