Instructions for use of PPS

Format：PPSCONTROL <switch> <polarity> <period> <pulse-width>

Description：This command controls the polarity, period, and pulse width of the pulse level output. You can also use this command to disable the PPS output.

Parameter:

【switch】 “enable” or “disable”, where “enable” means turning on PPS output (default is turned on), “disable” means turning off PPS output (once this field is set to disable, other parameters will be ignored)

【polarity】supports “positive” and “negative” , “positive” means high level pulse mode and  “negative” means low level pulse mode.

【period】in seconds, the update rate can be up to 10Hz.

【pulse-width】in microseconds, pulse-width should be less than half of period.

Example: PPSCONTROL ENABLE POSITIVE 1 1000

Format: CLOCKOFFSET <delay>

Description: This command sets the delay in PPS output in nanoseconds. Because of the following two factors, the PPS signal is delayed from the actual measurement time:

➤ Signal path delay from antenna to receiver

Using a cable with a 10ns delay will introduce a 10ns delay in the PPS output;

➤ Path delay from RF to digital part of receiver

Across different board types and signal processing methods, there are delays;

The default settings compensate for major shared delays, but users should adjust for residual delays based on antenna and cable differences. After setting, both instructions can save the settings through the "saveconfig" command, and the status of markcontrol can be queried through the "log sysconfig" command.

Parameter: A positive value of delay indicates delayed output, and a negative value indicates early output.

Example: CLOCKOFFSET -200  // Advance PPS output by 200 ns.

Test environment: oscilloscope tests PPS signal

(1) Test PPS signal output

Command: PPSCONTROL ENABLE POSITIVE 1 1000

During the test, the channel is adjusted to 1.000S. The oscilloscope waveform is as follows. After zooming in, you can see that the PPS pulse width is 1000.

(2) Test with different pulse output period and width

Command: PPSCONTROL ENABLE POSITIVE 0.5 500

During the test, the channel is adjusted to 1.000S. The oscilloscope waveform is as follows. After amplification, you can see that the PPS pulse output period is 0.5 and the PPS pulse width is 500.

(3) Disconnect with the antenna and continues PPS signal output

Command: PPSCONTROL ENABLE POSITIVE 1 1000 1   //Force output mode (positioning or not positioning)

Note 1: After disconnect with antenna, the PPS accuracy decrease as time goes.

Note 2: K8 firmware of 2022.6.10 and later versions are supported and can be obtained by contacting technical support.

All SinoGNSS&rsquo;s GNSS modules support PPS function. Please have a visit of our website and view detailed information.

https://www.comnavtech.com/Products/1625390818125623296.html