B&B Electronics 1939STB manual Byte, Shown in Table

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Byte 7

(Shown in Table 29)

Bits 7, 6, and 5 of byte 7 set the J1939 priority bits. Bit 7 is the MSB. Bit 5 is the LSB. To code a priority value = 6 set bit 7 = 1 bit 6 = 1 bit 5 = 0.

Bit 4 is the reserved bit - the J1939 specification sets this bit to zero. It may be used in the future therefore it is NOT hard coded. The user must set this bit to zero for every transmitted J1939 message.

Bit 3 is the data page bit and select page 0 or page 1and is set by the user.

Bits 2, 1, 0, are the MSB’s of the PDU format.

1939STB4600 Manual

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B&B Electronics Mfg Co Inc – 707 Dayton Rd - PO Box 1040 - Ottawa IL 61350 - Ph 815-433-5100 - Fax 815-433-5104

B&B Electronics Ltd – Westlink Commercial Park – Oranmore, Galway, Ireland – Ph +353 91 792444 – Fax +353 91 792445

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Contents Model 1939STB RS-232 to J1939 Converter CETable of Contents SAE Publications Introduction1939STB4600 Manual Description Physical Description Electrical SpecificationCommunication directed to the device Format Byte 3 Nibble Control ByteByte Message Received from the SAE-J1939 Bus Vendor String SetupInternal Functions Vendor StringRS-232 Baud Change Baud Rate SetupRS-232 Baud Rate Change cont’d Byte 5 UB3 Parity SetupWord Length Stop Bit SetupJ1939 Format External CommandsValid Codes for Byte Message Header SetupTwo Bit Values for Byte 5 Message Information J1939 Message InformationIntpnd ByteTransmit DLC DIR XTD Bit2J1939 Message Frame SAE-J1939 Control Header1939STB4600 Manual Shown in Table Byte1939STB4600 Manual Byte 1939STB4600 Manual Bytes 9 1939STB4600 Manual DIR Message Direction DLC Data Length CodeData Field ID Byte Reception of DataSAE-J1939 Bus Function Internal Messages Software Installation1939STB4600 Manual Message Transmission sending data to the 1939STB File Logging Saving Message InformationAppendix A. The Extended can / SAE-J1939 Message Frame Arbitration Field Appendix B. Example