EVO ORIN SYNC OUT Usage#
SYNC OUT Usage#
SYNC_OUT Pin Assignment#
Pin |
Signal |
1 |
PPS_GND |
2 |
RS232_RX |
3 |
RS232_TX |
4 |
SYNC_OUT1 |
5 |
GND |
6 |
PPS_OUT |
7 |
SYNC_OUT1_GND |
8 |
SYNC_OUT2_GND |
9 |
SYNC_OUT2 |
The SYNC OUT interface contains 2 channels of SYNC OUT signals and also contains PPS OUT function
SYNC OUT#
The main purpose of SYNC OUT is to allow the system to trigger external cameras at a fixed frequency.
Sync out Method#
The device can output a 1-30Hz pulse signal with a pulse width of 5ms through the Sync out pin to trigger an external sensor to start sampling. At the same time, the device will record the generation time of the rising edge of the pulse. After the sensor finishes sampling, the device will correlate the recorded time with the data sent back from this sensing as the timestamp of the data. So far, the system has obtained the system time of the sensor sampling and completed the synchronization.
Sync out Method Schematic (25Hz)
At the same time, the device also provides Sync Out synchronization function through the GMSL interface, please refer to the GMSL camera section for details.
Verification method for the synchronization function: Configure the sensor in external trigger synchronization mode and use ROSbag to capture packets to confirm if the sensor trigger frequency matches the frequency set in sync.cfg. If the deviation is less than 1Hz, it indicates that the Sync Out function is effective.
Data transfer time analysis
Test description: Set the frequency of Sync Out signal to 10Hz and measure the time interval (transfer time) from the rising edge of the Sync Out signal sent by the device to the device receiving the video frame.
IO Frame Transfer Timing Diagram.
Test Results of Frame Transfer Time.
The measurement results show that the average frame transfer time is 65.70ms.
**PPS OUT **
The PPS interface means that the MiVin device converts its own system time into a high-precision PPS signal and outputs it externally. This interface cannot be programmed, and is mainly used to achieve synchronization of the entire sensor system without the GPS device.