CAN Sym­bol Edi­tor Manu­al

The manu­al for CAN Sym­bol Edi­tor is only avail­ab­le in Ger­man. So here is a short ver­si­on with the main con­tent in English to help all our non-Ger­man-speakers.

1 Over­view

The CAN sym­bol edi­tor is a pro­gram to crea­te and edit sym­bol files which are used in CAN-Bus Tes­ter 2, CAN­touch and CAN­vi­si­on. The­se sym­bol files empower them able to inter­pret CAN messa­ges and decode them into a human read­a­ble form (sym­bo­lic deco­ding).

can messages symbolic decoding

2 Func­tions and con­trol

2.1 Sym­bol file struc­tu­re

2.1.1 Signals

Signals are the lowest level in a sym­bol file. They are used to descri­be the way, how an infor­ma­ti­on is rep­re­sen­ted in a CAN messa­ge. This is for ins­tan­ce a phy­si­cal para­me­ter, pre­sen­ting a value and a unit, but also sta­tus infor­ma­ti­ons.

For a basic descrip­ti­on you need :

  • the name
  • the num­ber of bits that the signal is using

More detail­ed optio­nal values can be :

  • the byte order, big endi­an (Moto­ro­la) or litt­le endi­an (Intel)
  • type of value (signed or unsi­gned, for ins­tan­ce float or dou­ble)
  • num­ber sys­tem of dis­play (deci­mal or hexa­de­ci­mal)
  • an unit
  • sca­ling and off­set
  • ran­ge

Also enu­me­ra­ti­ons are pos­si­ble, thats descrip­ti­ons of values (see 2.1.3 also).

2.1.2 Mul­ti­ple­xer

Mul­ti­ple­xer in the data field are used to trans­fer dif­fe­rent data with the same CAN ID. The value sets how the fol­lo­wing data bytes are assi­gned. For ins­tan­ce in CANo­pen SDO the first 3 bytes defi­ne, which para­me­ter of the index is trans­fe­red.

In our CAN sym­bol edi­tor only one mul­ti­ple­xer per messa­ge is allo­wed. It can have a length from 1 to 64 bit and can be free pla­ced wit­hin the data field. Mul­ti­ple­xer also can have value descrip­ti­ons (see 2.1.3)

2.1.3 Enu­me­ra­ti­ons

Enu­me­ra­ti­ons, thats descrip­ti­ons of values are making is pos­si­ble to con­nect values of signals or mul­ti­ple­x­ers to a string. Whil­de deco­ded, the­se strings are dis­play­ed. For ins­tan­ce you can dis­play “On” and “Off” to show the sta­te of a switch.

2.1.4 Messa­ges

Messa­ges rep­re­sent a CAN messa­ge with a cer­tain ID and can con­tain a mul­ti­ple­xer and dif­fe­rent signals. Becau­se only wit­hin the messa­ge the posi­ti­on of a signal is defi­ned and not wit­hin the signal, a signal can be used in dif­fe­rent messa­ges at the same time.

2.1.5 Watch­list

Watch­lists are used to have rela­ted messa­ges toge­ther. You can have often used messa­ges in one list.

2.2 User inter­face

2.3 Gene­ra­te a sym­bol file

2.3.1 Import from CAN data­ba­se (dbc)

The qui­ckest way to gene­ra­te a sym­bol file is to import a given Vec­tor CAN dbc file. After importing you can manu­al­ly edit every signal and messa­ge. See below.

2.3.2 Gene­ra­te manu­al­ly

  1. Open a new file.
    Click File and New.
  2. Crea­te signals and enu­me­ra­ti­ons
    Click on but­ton  to add a signal and open its edit win­dow. Give it a mea­ning­ful name and edit it.
    To use a value descri­ti­on switch value “dis­play” to “value descrip­ti­on” and klick . Now add your descrip­ti­on.
  3. Crea­te messa­ges
    Click sym­bol  to add a new messa­ge. Give a name, type of CAN id and id as well as the length of the data field.
    Move signals by using drag and drop into the win­dow. Dou­ble­click to open the edit win­dow whe­re you can defi­ne start bit posi­ti­on. Deci­de if the signal is a mul­ti­ple­xer or not. If yes that set the mul­ti­ple­xer value.
    Tab Lay­out shows the messa­ge and whe­re your signals are.
  4. Crea­te watch­lists
    Use com­ple­te messa­ges or signals only for your watch­lists.
  5. Edit file descrip­ti­on
    The descrip­ti­on is used in CAN­vi­si­on, CAN­touch and CBT2 to choo­se a cer­tain sym­bol file.