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Lasers are numbered sequentially starting with 0 for the first lower block laser to 31 for the last lower block laser; and 32 for the first upper block laser to 63 for the last upper block laser. For example, laser 32 fires simultaneously with laser 0, laser 33 fires with laser 1, and so on.
The sensor has an equal number of upper and lower block returns. Hence, when interpreting the delay table, each sequential pair of data blocks represents the upper and lower block respectively. Each upper and lower block data pair in the Ethernet packet has the same delay value.
The first firing of a laser pair occurs 419.3 µs after the issuance of the fire command. Six firings of each block takes 139 µs and then the collected data is transmitted. It takes 100 µs to transmit the entire 1248 byte Ethernet packet. This is equal to 12.48 Bytes/µs and 0.080128 µs/Byte. See Appendix E for more information.
A timing table, shown in Appendix G, shows how much time elapses between the actual capturing of a distance point and when that point is output from the device. By registering the event of the Ethernet data capture, you can calculate back in time the exact time at which any particular distance point was captured.
firMWare uPdate
From time to time Velodyne issues firmware updates. To update the sensor’s firmware:
1.Obtain the update file from Velodyne.
2.Connect the wiring harness
3.Power up the sensor.
4.Execute the update file; the screen below appears.
Figure 5. HDL software update screen capture.
5.Select the appropriate COM port. 6.Click Update.
7.The firmware is uploaded and check summed before it is applied to the flash memory inside the sensor. If the checksum is corrupted, no update occurs. This protects the sensor in the event of power or data loss during the update.
•If the update is successful, the sensor begins to spin down for a few seconds and then powers back up with the new firmware running.
•If the update is not successful, try the update several times before seeking assistance from Velodyne.
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