9.2.205 GMAC Express MAC IPG Stretch Register
| Name: | GMAC_EMAC_IPGS |
| Offset: | 0x10BC |
| Reset: | 0x00000000 |
| Property: | Read/Write |
| Bit | 31 | 30 | 29 | 28 | 27 | 26 | 25 | 24 | |
| IFG_24 | IFG_32 | ||||||||
| Access | R/W | R/W | |||||||
| Reset | 0 | 0 |
| Bit | 23 | 22 | 21 | 20 | 19 | 18 | 17 | 16 | |
| MIN_IPG[3:0] | |||||||||
| Access | R/W | R/W | R/W | R/W | |||||
| Reset | 0 | 0 | 0 | 0 | |||||
| Bit | 15 | 14 | 13 | 12 | 11 | 10 | 9 | 8 | |
| FL[15:8] | |||||||||
| Access | R/W | R/W | R/W | R/W | R/W | R/W | R/W | R/W | |
| Reset | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | |
| Bit | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 | |
| FL[7:0] | |||||||||
| Access | R/W | R/W | R/W | R/W | R/W | R/W | R/W | R/W | |
| Reset | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | |
Bit 31 – IFG_24 24-byte Interframe Gap
| Value | Description |
|---|---|
| 0 | Defines a minimum interframe gap of 12 bytes when IFG_32=0. |
| 1 | Defines a minimum interframe gap of 24 bytes when MIN_IPG=0. |
Bit 30 – IFG_32 32-byte Interframe Gap
| Value | Description |
|---|---|
| 0 | Defines a minimum interframe gap of 12 bytes when IFG_24=0. |
| 1 | Defines a minimum interframe gap of 32 bytes when MIN_IPG=0. |
Bits 19:16 – MIN_IPG[3:0] Minimum Interpacket Gap
Value of 0 indicates a minimum transmit interpacket gap defined by the configuration of IFG_24 and IFG_32.
Values of 1, 2 or 3 indicate a minimum transmit interpacket gap of 12 bytes.
For values of 4 to 15, the IPG is determined by multiplying this value by four, so values of 4 to 15 give an IPG range of 16 to 60 in four-byte increments. to a non-zero value means the IFG_24 and IFG_32 values will be ignored.
Bits 15:0 – FL[15:0] Frame Length
Bits 7:0 are multiplied with the previously transmitted frame length (including preamble). Bits 15:8 +1 divide the frame length. If the resulting number is greater than 96 and bit 28 is set in the Network Configuration register then the resulting number is used for the transmit interpacket gap. 1 is added to bits 15:8 to prevent a divide by zero. See MAC Transmit Block.