Datasheet
2009-2013 Microchip Technology Inc. DS60001156H-page 315
PIC32MX5XX/6XX/7XX
TABLE 24-5: PAD OPERATION
bit 6 VLANPAD: VLAN Pad Enable bit
(1,2)
1 = The MAC will pad all short frames to 64 bytes and append a valid CRC
0 = The MAC does not perform padding of short frames
bit 5 PADENABLE: Pad/CRC Enable bit
(1,3)
1 = The MAC will pad all short frames
0 = The frames presented to the MAC have a valid length
bit 4 CRCENABLE: CRC Enable1 bit
1 = The MAC will append a CRC to every frame whether padding was required or not. Must be set if the
PADENABLE bit is set.
0 = The frames presented to the MAC have a valid CRC
bit 3 DELAYCRC: Delayed CRC bit
This bit determines the number of bytes, if any, of proprietary header information that exist on the front of the
IEEE 802.3 frames.
1 = Four bytes of header (ignored by the CRC function)
0 = No proprietary header
bit 2 HUGEFRM: Huge Frame enable bit
1 = Frames of any length are transmitted and received
0 = Huge frames are not allowed for receive or transmit
bit 1 LENGTHCK: Frame Length checking bit
1 = Both transmit and receive frame lengths are compared to the Length/Type field. If the Length/Type field
represents a length then the check is performed. Mismatches are reported on the transmit/receive
statistics vector.
0 = Length/Type field check is not performed
bit 0 FULLDPLX: Full-Duplex Operation bit
1 = The MAC operates in Full-Duplex mode
0 = The MAC operates in Half-Duplex mode
REGISTER 24-24: EMAC1CFG2: ETHERNET CONTROLLER MAC CONFIGURATION 2 REGISTER
Note 1: Table 24-5 provides a description of the pad function based on the configuration of this register.
2: This bit is ignored if the PADENABLE bit is cleared.
3: This bit is used in conjunction with the AUTOPAD and VLANPAD bits.
Note: Both 16-bit and 32-bit accesses are allowed to these registers (including the SET, CLR and INV registers).
8-bit accesses are not allowed and are ignored by the hardware
Type AUTOPAD VLANPAD PADENABLE Action
Any xx0No pad, check CRC
Any 001Pad to 60 Bytes, append CRC
Any x11Pad to 64 Bytes, append CRC
Any 101If untagged: Pad to 60 Bytes, append CRC
If VLAN tagged: Pad to 64 Bytes, append CRC