Cypress S6J3200 Series, Manual

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CHAPTER 21:Ethernet MAC
S6J3200 Series Hardware Manual Document Number: 002-04852 Rev. *G 677
4.25.
IPG Stretch Register (ETHERNETn_stretch_ratio)
Description of IPG Stretch register is shown.
REGISTER_NAME ETHERNETn_stretch_ratio
OFFSET 0x0BC
ACCESS_SIZE W
MULTIPLE
NUMERIC_TYPE
OTHER
BIT_OFFSET 31 30 29 28 27 26 25 24
BIT_NAME Reserved
ACCESS_TYPE R0,WX
PROT_TYPE Wp
INITIAL_VALUE 0x00
BIT_OFFSET 23 22 21 20 19 18 17 16
BIT_NAME Reserved
ACCESS_TYPE R0,WX
PROT_TYPE Wp
INITIAL_VALUE 0x00
BIT_OFFSET 15 14 13 12 11 10 9 8
BIT_NAME ipg_stretch[15:8]
ACCESS_TYPE R/W
PROT_TYPE Wp
INITIAL_VALUE 0x00
BIT_OFFSET 7 6 5 4 3 2 1 0
BIT_NAME ipg_stretch[7:0]
ACCESS_TYPE R/W
PROT_TYPE Wp
INITIAL_VALUE 0x00
[bit31:16] Reserved
Always read "0". Writing has no effect.
[bit15:0] ipg_stretch: IPG Stretch
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.