B&B Electronics 1939STB manual XTD Bit2, Dlc Dir

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NEWDAT Bits 1and 0

Indicates if new data has been written into this slot by either the bus controller (receive messages) or the controller (transmit objects).

Byte 11

Table 26. Byte 11

Byte 11

Bit Function

Bit 7

Bit 6

Bit 5

Bit 4

Bit 3

 

Bit 2

Bit 1

Bit 0

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

DLC

 

 

 

 

 

 

XT

 

 

 

 

 

 

 

 

 

 

 

 

 

 

DIR

 

D

 

Number of data bytes (0 to 8)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Message direction: Transmit

 

 

 

 

 

 

 

 

 

 

 

 

 

1

 

 

 

 

 

 

Message direction: Receive

 

 

 

 

 

 

 

 

 

 

 

 

 

0

 

 

 

 

 

 

Extended identifier must be 1

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

1

 

 

 

Bit not used set to 0

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

X

 

Bit not used set to 0

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

X

DLC Bits 7, 6, 5 and 4

Data length code. The number of data bytes in the message.

DIR Bit 3

Direction. Defines if a message is transmit or receive.

Bit Set = 1

Transmit on reception of a remote frame matching the identifier.

Bit = 0

Receive. When a message is received with an identifier that matches the identifier of the message stored in this slot the data is stored in this slot.

XTD Bit2

Extended identifier. This bit should always be set to 1. Bits 1 and 0 are not used. To send a remote frame to Request Data, set up the message slot to Receive Mode, then set TXRQ (10). This will be cleared by the control once the data is sent or if the data is received before the remote frame could be transmitted.

18

1939STB4600 Manual

 

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 RS-232 to J1939 Converter CE Model 1939STBTable of Contents Introduction SAE Publications1939STB4600 Manual Description Electrical Specification Physical DescriptionCommunication directed to the device Format Control Byte Byte 3 NibbleByte Vendor String Setup Internal FunctionsVendor String Message Received from the SAE-J1939 BusBaud Rate Setup RS-232 Baud ChangeRS-232 Baud Rate Change cont’d Parity Setup Byte 5 UB3Stop Bit Setup Word LengthExternal Commands J1939 FormatMessage Header Setup Valid Codes for ByteMessage Information J1939 Message Information Two Bit Values for Byte 5Byte IntpndTransmit XTD Bit2 DLC DIRSAE-J1939 Control Header J1939 Message Frame1939STB4600 Manual Byte Shown in Table1939STB4600 Manual Byte 1939STB4600 Manual Bytes 9 1939STB4600 Manual DLC Data Length Code DIR Message DirectionData Field ID Byte Reception of DataSAE-J1939 Bus Function Internal Messages Installation Software1939STB4600 Manual Message Transmission sending data to the 1939STB Saving Message Information File LoggingAppendix A. The Extended can / SAE-J1939 Message Frame Arbitration Field Appendix B. Example