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Zynq-7000 AP SoC Technical Reference Manual www.xilinx.com 1319
UG585 (v1.11) September 27, 2016
Appendix B: Register Details
Once a statistics register has been read, it is automatically cleared.
Register (GEM) late_collisns
Register late_collisns Details
In statistics register block. Is reset to zero on a read and sticks at all ones when it counts to its maximum
value. It should be read frequently enough to prevent loss of data.
For test purposes, it may be written by setting bit 7 (Write Enable) in the network control register. Setting
bit 6 (increment statistics) in the network control register causes all the statistics registers to increment by
one, again for test purposes.
Once a statistics register has been read, it is automatically cleared.
Register (GEM) deferred_tx_frames
Field Name Bits Type Reset Value Description
reserved 31:10 ro 0x0 Reserved, read as 0, ignored on write.
excessive_collisns 9:0 ro 0x0 Excessive collisions - a 10 bit register counting the
number of frames that failed to be transmitted
because they experienced 16 collisions.
Name late_collisns
Software Name XEMACPS_LATECOLLCNT
Relative Address 0x00000144
Absolute Address gem0: 0xE000B144
gem1: 0xE000C144
Width 32 bits
Access Type ro
Reset Value 0x00000000
Description Late Collisions
Field Name Bits Type Reset Value Description
reserved 31:10 ro 0x0 Reserved, read as 0, ignored on write.
late_collisns 9:0 ro 0x0 Late collisions - a 10 bit register counting the
number of late collision occurring after the slot
time (512 bits) has expired. In 10/100 mode, late
collisions are counted twice i.e., both as a collision
and a late collision. In gigabit mode, a late
collision causes the transmission to be aborted,
thus the single and multi collision registers are not
updated.
Name deferred_tx_frames
Software Name XEMACPS_TXDEFERCNT