Analog Devices ADSP-SC58 Series Hardware Reference Manual page 2199

EMAC Programming Steps
1. For time stamping a transmitting frame, set the TTSE bit in the TDES0 register of the corresponding frame.
2. Extend the descriptor word length from 4 words to 8 words by setting the EMAC_DMA0_BUSMODE.ATDS
bit.
3. Configure bits 18–10 in the
specific types of received frames. Refer to the
4. Enable the PTP module by setting the EMAC_TM_CTL.TSENA bit.
5. Initialize the system time.
6. Verify the RDES4 register for the status of the received frame and the RDES6 and RDES7 registers for time
stamp nanoseconds and seconds value.
Programming for Auxiliary Time Stamps
1. Set the EMAC_IMSK.TS bit to enable PTP interrupts.
2. Set the EMAC_TM_CTL.TSENA bit to enable the PTP module.
3. Initialize system time.
ADDITIONAL INFORMATION: Whenever a rising edge on the auxiliary time stamp trigger pin is detected,
system time seconds and nanoseconds are captured and stored into 4-deep auxiliary time stamp FIFO. An aux-
iliary time stamp trigger interrupt occurs. The EMAC uses the EMAC_TM_STMPSTAT.ATSTS and the
EMAC_IMSK.TS bits to indicate the interrupt.
4. Read the contents of the FIFO one-by-one through
EMAC_TM_AUXSTMP_NSEC
EMAC_TM_AUXSTMP_SEC
the
EMAC_TM_AUXSTMP_SEC
5. Set the EMAC_TM_CTL.ATSFC bit to clear the FIFO.
Programming Fixed Pulse-Per-Second Output
Use the following procedure to program the fixed PPS output.
1. Enable the PTP module by setting the EMAC_TM_CTL.TSENA bit.
2. Output the PPS waveform by configuring the EMAC_TM_PPSCTL.PPSCTL0 bits and binary or digital roll-
over using the EMAC_TM_CTL.TSCTRLSSR bit. See
Programming Flexible Pulse-Per-Second Output
Use the following procedure to program flexible PPS output.
1. Enable the PTP module by setting the EMAC_TM_CTL.TSENA bit.
2. Set the EMAC_TM_PPSCTL.PPSEN bit to enable flexible PPS output.
31–108
EMAC_TM_CTL register so that the PTP module detects and time stamps only
EMAC_TM_CTL
registers. One level of the FIFO is cleared when the
register is read. Therefore, read the
register.
ADSP-SC58x/ADSP-2158x SHARC+ Processor Hardware Reference
register description for more information.
EMAC_TM_AUXSTMP_SEC
EMAC_TM_AUXSTMP_NSEC
Fixed Pulse-Per-Second
and
register before
Output.