Kvh1725 And Kvh1750 Baud Rate Conversion - Novatel OEM6 Integration Manual

Chapter 2 New for OEM7 – Firmware

2.4.6 KVH1725 and KVH1750 Baud Rate Conversion

The maximum baud rate of the COM ports on an OEM7 receiver is 460,800 bps. The KVH1750
and KVH1725 IMUs natively communicate at 921,600 bps, so they need to be modified to use
460,800 bps.
Though slower, 460,800 bps is more than adequate to transmit the data at the
required 200 Hz without any impact to performance.
There are two methods to change the KVH17xx series IMU baud rate. If an OEM6 receiver is
available, a command is available that will allow the receiver to change the IMU baud rate. If
not, a direct RS-422 connection at 921,600 baud is required to change the IMU baud rate.
IMU Direct Connection
This method requires a direct connection to the IMU at 921,600 baud over RS-
422.Make sure the RS-422 link used is capable of 921,600 baud as not all serial
ports are capable of that rate.
1. Open a command terminal at 921600 baud via an RS-422 serial link.
By default, the IMU will output 0.5 Hz binary messages which will help confirm you are con-
nected properly.
2. Issue the following two commands in sequence to enter configuration mode and change the
baud rate.
=CONFIG,1
=BAUD,460800
3. Upon completion of these commands, power cycle the IMU to boot up in the new baud rate.
4. Confirm the change by connecting to the IMU at 460,800 baud and verifying the incoming
messages.
The new baud rate configuration is saved to the IMU NVM automatically so the process is complete
and the IMU is ready for use with an OEM7 receiver.
Use an OEM6 Receiver Command
OEM6 firmware as of version OEM060630RN0000 (Dec 2016) includes the
IMUCONFIGURATION command that internally configures the KVH17xx IMU for SPAN com-
munication. Three sets of configuration options are available, two of which will allow user to
change the baud rate of the IMU to either 921,600 or 460,800. This provides customers upgrad-
ing to OEM7 an easy method to modify the baud rate. To change the IMU to 460800 baud, use
the following procedure:
1. Connect the KVH-17xx IMU (IMU-KVH1750 or IMU-KVH1725) to an RS422 capable OEM6
receiver communication port.
2. Issue the following command.
CONNECTIMU COM# IMU_KVH_17xx
OEM6 to OEM7 Integration Guide v1 151