PIC18F2480/2580/4480/4580
REGISTER 24-11: TXBnDLC: TRANSMIT BUFFER n DATA LENGTH CODE REGISTERS [0 ≤ n ≤ 2]
U-0
—
R/W-x
U-0
—
U-0
—
R/W-x
DLC3
R/W-x
DLC2
R/W-x
DLC1
R/W-x
DLC0
TXRTR
bit 7
bit 0
Legend:
R = Readable bit
-n = Value at POR
W = Writable bit
‘1’ = Bit is set
U = Unimplemented bit, read as ‘0’
‘0’ = Bit is cleared x = Bit is unknown
bit 7
bit 6
Unimplemented: Read as ‘0’
TXRTR: Transmit Remote Frame Transmission Request bit
1= Transmitted message will have TXRTR bit set
0= Transmitted message will have TXRTR bit cleared
bit 5-4
bit 3-0
Unimplemented: Read as ‘0’
DLC<3:0>: Data Length Code bits
1111= Reserved
1110= Reserved
1101= Reserved
1100= Reserved
1011= Reserved
1010= Reserved
1001= Reserved
1000= Data length = 8 bytes
0111= Data length = 7 bytes
0110= Data length = 6 bytes
0101= Data length = 5 bytes
0100= Data length = 4 bytes
0011= Data length = 3 bytes
0010= Data length = 2 bytes
0001= Data length = 1 bytes
0000= Data length = 0 bytes
REGISTER 24-12: TXERRCNT: TRANSMIT ERROR COUNT REGISTER
R-0
R-0
R-0
R-0
R-0
R-0
R-0
R-0
TEC7
TEC6
TEC5
TEC4
TEC3
TEC2
TEC1
TEC0
bit 7
bit 0
Legend:
R = Readable bit
-n = Value at POR
W = Writable bit
‘1’ = Bit is set
U = Unimplemented bit, read as ‘0’
‘0’ = Bit is cleared x = Bit is unknown
bit 7-0
TEC<7:0>: Transmit Error Counter bits
This register contains a value which is derived from the rate at which errors occur. When the error
count overflows, the bus-off state occurs. When the bus has 128 occurrences of 11 consecutive
recessive bits, the counter value is cleared.
© 2009 Microchip Technology Inc.
DS39637D-page 291