B&B Electronics HVD100A3 manual J1939 Commands

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J1939 Commands

The J1939 protocol is similar to the J1708 protocol.

The message starts with Start of Frame byte 01. The number of control bytes will be 06. The control code for J1939 is 02. The function codes (XX) are as follows:

00=Sets receive function off 01=Sets receive on 02=Transmits a message with data 04=Set mask

19=filter 1 set on 18=filter 1 set off 29=filter 2 set on 28=filter 2 set off 39=filter 3 set on 38=filter 3 set off 49=filter 4 set on 48=filter 4 set off

Function codes are shown in detail below.

Before operating the HDV100A3 in the J1939 mode it is

recommended that the baud rate be set to 115.2kb. This is done by sending the following code: (01, 05, 08, 01, 03, 04, 00, 00 16). After sending this command the baud rate of the sending device (PC) must also be changed.

Because of the difference in baud rates between the J1939 bus and the RS-232 serial bus, the HDV100A3 may miss messages on the J1939 bus. This depends on bus load, message length, and filter settings.

Sending any message with a control code of (02) to the J1939 bus stops the operation on the J1708 bus. If you wish to restart operation on the J1708 bus you must send the start J1708 reception message (01, 02, 01, 11, 00, 15). Sending this message stops operation on the J1939 bus.

Function codes 00 and 01, Receive OFF, ON operate together to control a receive register. Sending the command (01, 02, 02, 01, 00, 06) starts reception on the J1939 bus. This command resets the filter mask to all zeros (don’t care). All bus traffic is then received. However, it may not be possible to send all messages to the PC side. Any message that is not serviced before the next message is received will be overwritten by the new message. Sending the command (01, 02, 02, 00, 00, 05) turns off the receiver. It is

HDV100A3 Command & Response Manual-1306cr

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B&B Electronics -- 707 Dayton Rd. -- PO Box 1040 -- Ottawa, IL 61350

PH (815) 433-5100 -- FAX (815) 433-5104

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Contents HDV100A3 Command Response Protocol Page Table of Contents Do Not Transmit Any Messages to the network Introduction Intelligent Mode VerificationControl Field Structure Intelligent Mode Command ProtocolIntelligent Mode Message Structure SOFFormatting the Control Bytes Detailed Description of General Function Codes Command AcknowledgementRS-232 Baud Rate Setup HDV100A3 Command & Response Manual-1306cr Setting Baud 1, Baud Baud Rate Setup Table UB3 Baud Rate ExampleByte Byte Function Number Value Hex Reply from HDV100A3 Byte Function Number ValueFunction code 20 = stop time stamping Vendor Information Master Reset CommandByte Byte Value Byte Function Number Hex J1708 CommandsReceiving Data from the J1708 Bus Function code 10 hex stop receive Priority Byte Value Binary Value Hex Value Transmitting Data to the J1708 BusID bytes 9 = transmit OK Set Filter Off Byte Function Number Value J1708 Message FilterSet Filter Active Byte Function Number Value Data Broadcast MessageByte 6 Priority Values Byte 4 ValuesJ1939 Commands Stop Receive on J1939 Bus Start Receive on J1939 BusArbitration Field Y1, Y2, Y3, Y4 Message received from the HDV will be formatted as follows Set Mask Transmit Data to J1939 BusMSB-1 MSB-2Set Filter 1 to HDV100A3 Command & Response Manual-1306cr J1939 Header Worksheet DEC HEX Error Codes
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