DocID13902 Rev 15 1044/1128
RM0008 Ethernet (ETH): media access control (MAC) with DMA controller
1064
29.8.3 IEEE 1588 time stamp registers
This section describes the registers required to support precision network clock
synchronization functions under the IEEE 1588 standard.
Ethernet PTP time stamp control register (ETH_PTPTSCR)
Address offset: 0x0700
Reset value: 0x0000 0000
This register controls the time stamp generation and update logic.
Ethernet PTP subsecond increment register (ETH_PTPSSIR)
Address offset: 0x0704
Reset value: 0x0000 0000
313029282726252423222120191817161514131211109876543210
Reserved
TTSARU
TSITE
TSSTU
TSSTI
TSFCU
TSE
rw rw rw rw rw rw
Bits 31:5 Reserved
Bit 5 TSARU: Time stamp addend register update
When this bit is set, the Time stamp addend register’s contents are updated to the PTP block
for fine correction. This bit is cleared when the update is completed. This register bit must be
read as zero before you can set it.
Bit 4 TSITE: Time stamp interrupt trigger enable
When this bit is set, a time stamp interrupt is generated when the system time becomes
greater than the value written in Target Time register. When the Time Stamp Trigger interrupt
is generated, this bit is cleared.
Bit 3 TSSTU: Time stamp system time update
When this bit is set, the system time is updated (added to or subtracted from) with the value
specified in the Time stamp high update and Time stamp low update registers. Both the
TSSTU and TSSTI bits must be read as zero before you can set this bit. Once the update is
completed in hardware, this bit is cleared.
Bit 2 TSSTI: Time stamp system time initialize
When this bit is set, the system time is initialized (overwritten) with the value specified in the
Time stamp high update and Time stamp low update registers. This bit must be read as zero
before you can set it. When initialization is complete, this bit is cleared.
Bit 1 TSFCU: Time stamp fine or coarse update
When set, this bit indicates that the system time stamp is to be updated using the Fine
Update method. When cleared, it indicates the system time stamp is to be updated using the
Coarse method.
Bit 0 TSE: Time stamp enable
When this bit is set, time stamping is enabled for transmit and receive frames. When this bit
is cleared, the time stamp function is suspended and time stamps are not added for transmit
and receive frames. Because the maintained system time is suspended, you must always
initialize the time stamp feature (system time) after setting this bit high.
To Next Page
Loading...
Need help?
General
