Time Sync Registers
BCM5718 Programmer’s Guide
Broadcom
®
January 29, 2016 • 5718-PG108-R
Page 162
EAV REF-COUNT SNAP-SHOT LSB[0] REG [Offset 0X6910]
This LSB and MSB pair captures the EAV Reference Count when externally triggered by the desired TimeSync/
APE_GPIO pin – a toggle serves a trigger. The only legal sequence of accessing this pair is Read-LSB followed
by Read-MSB.
EAV REF-COUNT SNAP-SHOT MSB[0] REG [Offset 0X6914]
EAV REF CORRECTOR REG [Offset 0x6928]
TX TIME STAMP LSB REG [Offset 0x05C0]
This LSB and MSB pair captures time-stamp of transmit packets when marked to do so. The only legal sequence
of accessing this pair is Read-LSB followed by Read-MSB. Once the LSB is read, the pair attains a frozen state,
and is unfrozen immediately after a subsequent MSB read – if another TX packet passes to the wire between
these two reads, it’s time stamp capture request is ignored by hardware.
Stop EAV Ref Count
1
RW
0
Reset EAV Ref Count
0
W1C
0
Name
Bits
Access Default Value Description
EAV Reference Count
Snap-shot [lower half]
31:0 RO
U
LSB of the EAV Reference Count as snapshotted by
TimeSync/APE_GPIO
[2:0] shall always be 000
Name
Bits
Access Default Value Description
EAV Reference Count
Snap-shot [Upper half]
31:0 RO
U
MSB of the EAV Reference Count as snapshotted by
TimeSync/APE_GPIO
Name
Bits
Access Default Value Description
Correction Enable
31
RW
0
Write a 1 to Enable the Correction feature.
Correction Sense
30
RW
0
If 0, the correction is an addition
If 1, the correction is a subtraction
Reserved
29:24 RO
0x00
Reserved
Correction Value
23:0 RW
0x000001
This value is accumulated in an accumulator every
EAV REF CLK tick until it overflows – upon which the
EAV REF COUNT is corrected by a 8ns unit and the
acc is reloaded.
A 0x0 value is not permissible.
Name
Bits
Access Default Value Description