Manual delay setting

Manual Delay Setting

We will now try manually setting delays for the trace data signals based on the RTM log.

1. Look at the last set of RTM_DELAY_X entries displayed in the log.txt file (where X is a number from 1-32).
   Note: You will set the DSTREAM-PT DELAY_TRACE_SIGNAL configuration items in the platform configuration's .sdf, .rcf, or .rvc file based on the values shown for RTM_DELAY_X.  What value you use is based on the RTM_DELAY_X values in the log.

   • If the all the RTM_DELAY_X entries have a least significant byte of 0x00 or 0x1f, you will set use a trace data signal delay value of 0x10.
   • If a few of the RTM_DELAY_X entries have a least significant byte of 0x00 or 0x1f, but some of the least significant byte values are between 0x00 and 0x1f, you will use a trace data signal delay of one of the non-0x00 or non-0x1f values.

   The DELAY_TRACE_SIGNAL values are based in picoseconds at a 82 picosecond resolution, so you will need to convert the least significant byte value shown in RTM_DELAY_X using the below formula:

   DELAY_TRACE_SIGNAL_X = converted to decimal(RTM_DELAY_X bits[7:0]) * 82

   For example, a least significant byte of 0x10 equals a trace data signal delay of 1312.

2. Save a copy of the .sdf, .rcf, or .rvc file before any modifications are made.
3. Open the platform configuration .sdf, .rcf, or .rvc as a text file.
4. Set a bit for every bit of the target's trace port size to RTM_INITIAL_DELAY_OVERRIDE_ENABLES configuration item.  For example, if you have a 16 bit trace port, then you would set <RTM_INITIAL_DELAY_OVERRIDE_ENABLES Type = "Int32">0xFFFF</RTM_INITIAL_DELAY_OVERRIDE_ENABLES>.  This will override all the delay times used for all the trace data signals.

5. Set the DELAY_TRACE_SIGNAL_X configuration items to the trace data delay value determined in step 1.  For example, if you want to set a trace data delay value of 1312 ps to every trace data signal in a 16-bit trace port, you set <DELAY_TRACE_SIGNAL_X Type = "Int32">1312</DELAY_TRACE_SIGNAL_X> where X is 1-16.

   Note: You only need to set trace data signal delays for the size of your trace port.  For example, if you have a 4-bit trace port, you set delays for DELAY_TRACE_SIGNAL_1 - 4 and leave the rest unaltered.

6. Click File → Save.
7. Start a new dbghw_log_client session using a new log file as output (like <writable path>\log3.txt).
8. If you are editing the .sdf, .rcf, or .rvc outside Arm Development Studio, rebuild the configuration database in Arm Development Studio by clicking Window → Preferences → Arm DS → Configuration Database → Rebuild database.
9. If you are currently connected to the target with Arm Development Studio, disconnect and then re-connect to the target.
10. Perform the trace capture again.
    Note:  You may need to run the capture for several seconds to ensure good output.