DBC parameter conversion to RealDash CAN format

Connectivity RealDash CAN
1

Hi, I am looking for some guidance regarding translation of DBC parameters into RealDash CAN equivalent. I have been using Python with cantools library to achieve this, but recently noticed an anomaly, which I cannot rationalise other than there being some error in the Python translation although I have many working signals / values already.

720_B2 is the gear shift (P, R, N, D) and 720_B3 is the manual selection (4, 3, 2, L).

For 720_B2 using RealDash CAN Monitor in decimal I get (P=9, R=2, N=12, D=16), however, logging these same parameters in RealDash DataLogging gives me (P=18, R=4, N=24, D=32) with same doubling effect for 720_B3

DBC

BO_ 720 MP10: 8 FJ_CRUISER
SG_ ID720_B2 : 23|8@0+ (1,0) [0|0] “” Vector__XXX
SG_ ID720_B3 : 31|8@0+ (1,0) [0|0] “” Vector__XXX

RealDash

frame canId=“0x2d0” endianess=“big”>
value name=“MP: ID720_B2” startbit=“23” bitcount=“8” units=“None” signed=“false” rangeMin=“None” rangeMax=“None” /value
value name=“MP: ID720_B3” startbit=“31” bitcount=“8” units=“None” signed=“false” rangeMin=“None” rangeMax=“None”/value
/frame

2

By way of an update, I realised the Python code I was using to convert from DBC to RealDash XML needed to be recoded.

Whilst the conversion of single bit values using startbit / bitcount was fine; this was not the case with multiple bit and byte values, which was introducing an undesirable bit shift.

Apart from single bit values, the code now converts using offset / length only and this is now working fine. It also explains why canbus sniffing values has been so troublesome.

1 Like
3

translation so can i run this code in realdash ?

BO_ 947 BodyInformation_3_MS: 8 XXX
SG_ CamraDefog_B_Req_UB : 58|1@0+ (1,0) [0|0] “” XXX
SG_ TrStats_D_Actl_UB : 48|1@0+ (1,0) [0|0] “” XXX
SG_ RearFog_Lamp_Dbnce_UB : 49|1@0+ (1,0) [0|0] “” XXX
SG_ TrStats_D_Actl : 13|2@0+ (1,0) [0|0] “” XXX
SG_ CamraDefog_B_Req : 40|1@0+ (1,0) [0|0] “” XXX
SG_ RearFog_Lamp_Dbnce : 0|1@0+ (1,0) [0|0] “” XXX
SG_ CarMode : 53|4@0+ (1,0) [0|0] “” XXX
SG_ Day_Night_Status : 15|2@0+ (1,0) [0|0] “” XXX
SG_ Parklamp_Status : 3|2@0+ (1,0) [0|0] “” XXX
SG_ Dimming_Lvl : 31|8@0+ (1,0) [0|0] “” XXX
SG_ Litval : 23|8@0+ (1,0) [0|0] “” XXX
SG_ Mfs_Turn_Stalk_SW_Status : 11|2@0+ (1,0) [0|0] “” XXX
SG_ PwMdeExten_D_Actl : 63|5@0+ (1,0) [0|0] “” XXX
SG_ STR_WHL_ANGLE : 39|15@0+ (0.1,-1000.0) [0|0] “Degrees” XXX
SG_ Turn_Seq_Cmd_Right : 7|2@0+ (1,0) [0|0] “” XXX
SG_ Turn_Seq_Cmd_Left : 5|2@0+ (1,0) [0|0] “” XXX
SG_ Smart_Wiper_Motor_Stat_UB : 8|1@0+ (1,0) [0|0] “” XXX
SG_ Smart_Wiper_Motor_Stat : 55|2@0+ (1,0) [0|0] “” XXX
SG_ Mfs_Turn_Stalk_SW_Status_UB : 9|1@0+ (1,0) [0|0] “” XXX
SG_ reserve : 1|1@0+ (1,0) [0|0] “” XXX

4

Hi @CommaL attaching the XML translation, noting the single bit units="bit’ will be fine as will the full byte values shown with offset / length, but you may have to tweak the startbit for the 2 bit, 5 bit, and 15 bit signals in your list to get these to work
commal.xml (3.1 KB)

5

@CommaL please disregard first version, I noticed a few conversion errors, now corrrected as attached
commal.xml (3.1 KB)

6

Thank you very much for your answer. I found the codes on the internet and you translated them, unfortunately it did not work.
My car is ford fiesta mk8 screen. I have codes that I work on my desk. Please help me if I share.

//Vehicle Alarm + Parking Brake
opSend(0x3C3, 0x00, B11111111, handbrake, brakeApplied, 0x00, 0x00, 0x00, 0x00);
//Bytes 1/2: B11111111=Alarm
//Byte 3: B00010000=Park Brake

//ABS
opSend(0x416, 0x0E, 0x00, 0x00, 0x00, 0x00, tc, 0x00, 0x00);
//Byte 6: B00000100=Slow flashing TC, B00000010=Solid TC Light
//Byte 7: B10000000=Rapid flashing ABS, B01000000=Solid ABS

//TPMS
opSend(0x3b4, tpms, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00);
//Byte 1: 49=Shows Low Tire Pressure Menu, B00000100 shows still tire warning, B00001000 shows flashing tire warning
//Byte 2: Highlights Front R and L tires
//Byte 3: Same as above but rear

//ECU
opSend(0x421, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00);
//Byte 1: B00001000=Flashing CEL, B00000100=Solid CEL

//Charging System
opSend(0x42C, 0x00, 0x00, 0xA6, 0x00, 0x00, 0x00, 0x00, 0x00);
//Byte 2: 17=Charge Light (No Message on Screen)

//Power Steering
opSend(0x877, 0x20, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00);

//Language?
opSend(0x191, 65, 17, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00);
//Byte 1: Units; 65=KM and CELSIUS
//Byte 2: 17=English, 35=German

//Outside Temp
opSend(0x3B3, 0x00, 0x00, 0x00, 0x00, 125, 0x00, 0xFF, 0x00);
//Byte 5: Outside Temp Value → 125=22°C

//Front Camera
opSend(0x3D8, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00);

//Tractioncontrol
opSend(0x46A, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00);

//High Beam + Auto Hed
opSend(0x46B, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, fullBeam);
//Byte 8: B00110000=High Beam

// RPM
opSend(0x42F, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, rpmgate, finetune);

// Speedometer INOP
opSend(0x202, 0x40, 0x00, 0x00, 0x00, distance, distance, speed, finetuner);

opSend(0x591, 0x91, 0x00, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF); // Keep alive signal
opSend(0x3B2, 0x45, 0x00, 0x00, 0x8E, B00000000, 0x00, B00000000, 0x00); //Ignition
opSend(0x179, 0x00, 0x00, 0x00, 0x00, 0x10, 0x00, 0x00, 0x00); //Odometer and Service
opSend(0x156, 0x00, 0x00, 0x00, 0x00, 0x23, 0x00, 0x00, 0x00); //Coolant
opSend(0x04C, 0x00, 85, 85, 0x00, 0x00, 0x00, 0x00, 0x00); //Airbag
opSend(0x213, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00); //Parking Brake (Fusion 2013)
opSend(0x3C3, 0x00, B11111111, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00); //Vehicle Alarm + Parking Brake
opSend(0x416, 0x0E, 0x00, 0x00, 0x00, 0x00, B00000000, B00000000, 0x00); //absLight
opSend(0x3b4, 0, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00); //TPMS
opSend(0x421, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00); //ECU
opSend(0x42C, 0x00, 0x00, 0xA6, 0x00, 0x00, 0x00, 0x00, 0x00); //Charging System
opSend(0x877, 0x23, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00); //Power Steering
opSend(0x191, 65, 17, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00); //Language?
opSend(0x3B3, 0x00, 0x00, 0x00, 0x00, 100, 0x00, 0xFF, 0x00); //Outside Temp
opSend(0x3D8, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00); //Front Camera
opSend(0x46A, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00); //Tractioncontrol
opSend(0x46B, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, B00000000); //High Beam + Auto Hed

7

@CommaL I did the first two frames for you as attached. Suggest you get a copy of Kvaser Database Editor which is great for managing the source DBC file, if you send me the DBC file I am happy to convert to RealDash XML or alternatively I can
ford_fiesta_can.xml (1.1 KB)
send you the Python progam I use.

1 Like
8

hI mmain .Could you please help me in converting DBC to xml format. I have a DBC file from Rusefi can Verbose and I would like to apply it in Realdash for my Subaru Legacy. Can you help me do it. Thank you in advance.

9

subaru.xml (10.9 KB)
Try this

10

subaru.xml (9.7 KB)
Please ignore earlier and use this instead; once confirmed working it would be worthwhile removing “name” entries in favour of targetId to align with RealDash