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Keypad specific values
The default address of the keypad is set to 0x80 (0d128). It can be modified either by start up
with the automatic Address claiming procedure (explained in 9.3), by Commanded Address
message which is described in SAE J1939-81 or in our case with the proprietary Source
Address Command (as described in 9.4.3).
The most important PGNs for communicating with the keypad are the Proprietary A and
Proprietary B PGNs. All of the functions of the keypad are mapped to those. Basic functions
are described in this manual. All details and all functions can be found in the corresponding K-
Matrix.
Installation in a network
After connecting the keypad electronically to the network an address claim procedure is started
automatically (as described in JAE J1939-81).
The software of a J1939 CAN device is the so called Controller Application (CA). Every CA is
equipped with a unique address and an associated device name. To determine which CA
sends a message each message contains a source address. There are predefined ranges for
those addresses and they range from 0 to 255.
In the case of the Rugged Keypad a range of the source address is limited to the range
between 128 and 247. Default value for the address is 128.
The address claim procedure sends a message with the corresponding parameter group
number as specified by the J1939 standard with the desired source address and a 64 bit device
name. This device name contains information about the Application and describes the main
function. If there are other devices in the J1939 CAN network that already use the desired
source address the device name with the higher priority claims the address.
Example of default address claim message as sent by the keypad module with default values:
CAN-ID
DLC Data
Byte 0
Data
Byte 1
Data
Byte 2
Data
Byte 3
Data
Byte 4
Data
Byte 5
Data
Byte 6
Data
Byte
7
0x18EEFF80 8
0xFF
0xFF
0x1F
0x74
0x00
0x87
0x00
0x80
For the explanation which data byte contains which information please refer to the
corresponding K-matrix or the SAE document SAE J1939-81. For practical use of the keypad
it should be avoided to use the address claim functionality to manage the addresses of two or
more keypads on the bus. It has to be taken into account that the keypads don’t keep their
addresses assigned by address claim after a power-on-Reset. That means that the procedure
of address claim starts after every power-on-reset and the keypads can be get different
addresses each time they are powered on. The best way to use the keypad is to configure the
node-ID as explained in 9.8.2.
If there is no address conflict detected the keypad will start with its normal communication and
claims the source address 128 (0x80).
