XGauge (CAN-bus) for Dummies...

[Dan]

EDIT:

• Excel file with all the codes I hacked together.
• Jump to post 21 where I explain how to program the XGauge.

Ok... I feel pretty stupid but I finally get it now. I've been trying for weeks to get my head around what XGauge was doing. Took WFEC and the revelation that we were flying blind without Battery Amps on the Prius to focus my efforts.

Well here's what I found. First let qualify that this is CAN-bus only. Since I'm a Prius Pilot that's all I've been focused on. So what I've found out is that there are two types of CanBus requests. Passive (snooping the bus) and active. Passive is kinda like ease-dropping on a conversation... the data is just there. Passive is like asking a direct question and expecting a direct answer.

Now after doing a bit of digging there is lots of data out there for the taking... Here's what I "think" we can get:

Passive
L/R GForce = TXD { 0x002A }
F/B GForce = TXD { 0x002B }
Steering degrees L/R = TXD { 0x002D }
Brake engagement % = TXD { 0x0038 }
Speed (decameters / hour ) = TXD { 0x00BC }
Gas pedal position = TXD { 0x024C }
Battery Temp = TXD { 0x03C3 }
Ignition timining = TXD { 0x052E }
EV button (on/off) = TXD { 0x0521 }
Gas Fill Level = TXD { 0x05AC }

Active
Battery SoC = TXD { 0x07E321CE }
Battery Temp = TXD { 0x07E321CF }
MG 1/2 RPM = TXD { 0x07E221C3 }
MG 1/2 RPM = TXD { 0x07E221C4 }

Now there is some other stuff like Headlights (on/off) and stuff like that that I'm not that interested in, but this data all looked pretty cool. I haven't gotten that deep into it so don't pepper me with Q's yet, but please help my "Teach Dan XGauge" thread.

If you look for the Passive commands and you can't find them, it's because the passive TXD is derived by taking the ID, left padding it with zeros and XOR'ing it wish 0x0008. Now all this is Attila Vass data, so I don't know if Ron has already tried and failed to get these to work, or if he just figured, no prius driver in his right mind would be interested in how many lateral G's he pulls in a turn. I'm obviously not in my right mind

GForce sensor is the first one I want to try to get working!

Now once I get the TXD working we can work on the rest... Here's my current reference set:

Attila Vass Can Dump (Excel)
2way's XGauge Coding walkthru
PriusChat XGauge Coding walkthru (Passive Can)
Prius Tech Info
PriusChat Known SGII Glide Bug

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[bestmapman]

Great thread dan. Can we also write to the can bus. What I am thinking is, can we command engine off when in Neutral. Thus having a glide above 42 MPH.

[Dan]

Alright... First new XGauge is tested and Verified.

EV Button ( On / Off )
TXD: 05 21
RXF: 01 05 22 29 00 00
RXD: 31 01
MTH: 00 01 00 01 00 00
NAM: EVb

What you'll see on your Gauge is
EVb ON
EVb OFF

And the fun part... It's real-time. No polling delay since it's packet sniffing. I leave it as a homework assignment to decode the logic I used to arrive at the XGauge coding.

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[TheForce]

Looks like your doing what I had planed to do. I just got my SG yesterday. After working with the RAW can-view data and the can-decoder software I'm now familiar with the raw CAN hex data and I know how to convert it.

I'm Not familiar with the way the xgauge does the converting yet. I think I will need an example of how you get from Vass's info to what the SG displays. I'm sure its simple.

I'm really interested seeing the Gforce in real time.

[Dan]

Look through the refereces I listed in the OP and all the XGauge stuff is pretty well explained.

Here's the next dump of XGauges. These are blind codes (untested) so I don't know which work:

Battery Temp (Max)
TXD: 03 C3
RXF: 01 03 02 3B 00 00
RXD: 38 08
MTH: 00 01 00 01 00 00
NAM: BTc

Battery Temp (Min)
TXD: 03 C3
RXF: 01 03 02 3B 00 00
RXD: 30 08
MTH: 00 01 00 01 00 00
NAM: BTc

Left / Right GForce
TXD: 00 2A
RXF: 01 00 02 22 00 00
RXD: 10 10
MTH: 00 01 00 01 FE 00
NAM: LRg

Front / Back GForce
TXD: 00 2B
RXF: 01 00 02 23 00 00
RXD: 10 10
MTH: 00 01 00 01 FE 00
NAM: FBg

Alignment (stear left / right)
TXD: 00 2D
RXF: 01 00 02 25 00 00
RXD: 10 10
MTH: 00 01 00 01 00 00
NAM: Slr

Break Pedal Position
TXD: 00 38
RXF: 01 00 02 30 00 00
RXD: 30 08
MTH: 00 64 00 80 00 00
NAM: BPs %

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[TheForce]

I just tried out the G force setting while sitting still and here is what I seen.

LRg stays at about 3 but if I shake the car the number jumps around a bit.

FBg stays at 1 even when I shake the car.

I will be leaving for work in about an hour and I will report back with my trip results.

[Dan]

Yeah, it's just a flat hex value. I haven't scaled it to actuall GForce. It should go way positive on a hard left and way negative on a hard right.

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[Dan]

OK.. got another two coded up but untested....

Speed down to the hundredth place. I always disliked the fact that the speedo doesn't have a decimal point. Well now it does. The MTH was tricky on this so I'll actually be surprised if I got it spot on with the first attempt.

kph xx.xx
TXD: 00 BC
RXF: 01 00 42 B4 00 00
RXD: 38 10
MTH: 03 E8 04 00 00 00
NAM: kph xx.xx

mph xx.xx
TXD: 00 BC
RXF: 01 00 42 B4 00 00
RXD: 38 10
MTH: 08 D8 0E 93 00 00
NAM: mph xx.xx

[TheForce]

Gforce does work. Only problem is that the SG display rate is way too fast. You might have to divide the data by something to get it to slow down or to get an actual 0.00 gforce value.

[Dan]

All these passive commands are gonna refresh wicked fast. Can't be helped... that's how many canbus packets are flooding the bus. You could do some creative binary shift operations to clip off the last 4 bits or something. That should slow the jitter.

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