Receive Elasticity Buffer Size: This field controls the Receive Elasticity Buffer which allows for frequency variation tolerance between the 50MHz RMII clock and the recovered data. The following values indicate the tolerance in bits for a single packet. The minimum setting allows for standard Ethernet frame sizes at ±50ppm accuracy. For greater frequency tolerance, the packet lengths may be scaled (for ±100ppm), divide the packet lengths by 2).
0x0 = 14 bit tolerance (up to 16800 byte packets)
0x1 = 2 bit tolerance (up to 2400 byte packets)
0x2 = 6 bit tolerance (up to 7200 byte packets)
0x3 = 10 bit tolerance (up to 12000 byte packets)
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