SOC-Meter User Guide and Firmware Updates

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Sounds promising! What are the CANbus message bytes and interpretation for "Real SOC"?
I've looked, but can't find a thread in Engineering that describes it.
 
Gary flashed my Gid meter with v 1.09 today. I'm already enjoying having SOC displayed. Found that I can use it to make a quick estimate of distance til empty by multiplying the SOC by 70 miles at indicated 4.0 mi/kWh, since I know that my LEAF can go a bit more than 70 miles at that efficiency. So even though we think SOC is less useful than Gids, it is quite useful provided you know your LEAF's full charge range capability.

Should we start a thread on user experiences with "real" SOC?
 
Boomer23 said:
Gary flashed my Gid meter with v 1.09 today. I'm already enjoying having SOC displayed. Found that I can use it to make a quick estimate of distance til empty by multiplying the SOC by 70 miles at indicated 4.0 mi/kWh, since I know that my LEAF can go a bit more than 70 miles at that efficiency. So even though we think SOC is less useful than Gids, it is quite useful provided you know your LEAF's full charge range capability.

Should we start a thread on user experiences with "real" SOC?

how does the SOC and GID % compare to each other?
 
DaveinOlyWA said:
Boomer23 said:
Gary flashed my Gid meter with v 1.09 today. I'm already enjoying having SOC displayed. Found that I can use it to make a quick estimate of distance til empty by multiplying the SOC by 70 miles at indicated 4.0 mi/kWh, since I know that my LEAF can go a bit more than 70 miles at that efficiency. So even though we think SOC is less useful than Gids, it is quite useful provided you know your LEAF's full charge range capability.

Should we start a thread on user experiences with "real" SOC?

how does the SOC and GID % compare to each other?
Depends on how much the battery has degraded. SOC will always charge to 80% or ~95% on an 80% or 100% charge respectively but GID% will slowly decline with age.
 
DaveinOlyWA said:
Boomer23 said:
Gary flashed my Gid meter with v 1.09 today. I'm already enjoying having SOC displayed. Found that I can use it to make a quick estimate of distance til empty by multiplying the SOC by 70 miles at indicated 4.0 mi/kWh, since I know that my LEAF can go a bit more than 70 miles at that efficiency. So even though we think SOC is less useful than Gids, it is quite useful provided you know your LEAF's full charge range capability.

Should we start a thread on user experiences with "real" SOC?

how does the SOC and GID % compare to each other?

Here's a tiny bit of data from the past few days to illustrate how SOC% compares with Gids. These are data sets from readings that I take in the morning after a charge and in the evening at the end of the day's driving. Both of these charges happened to be to 100% with no end timer set, though I usually charge to 80%. GOM readings are included for completeness only. Also, my car still has 12 capacity bars.

GOM / Charge Bars / Gid % / Raw Gids / SOC % / Voltage / mi/KWh for day

15 mi / 2 bar / 25.2% / 71 / 30.8% / 367 V / 4.0 mi/kWh End of Day Oct 13
91 mi / 12 bar / 87.1% / 245 / 93.1% / 393 V / Start of day after 100% charge
51 mi / 6 bar / 50.8% / 143 / 54.4% / 378.5 V / 4.2 mi/kWh End of Day Oct 14
101 mi / 12 bar / 87.9% / 247 / 94.0% / 392.5 V / Start of Day after 100% charge
71 mi / 8 bar / 66.9% / 188 / 70.0% / 384 V / 4.0 mi/kWh End of Day Oct 15
 
This firmware update is most definitely of interest to me, and I applaud Gary for making it happen. I'll have to make it to another SoCal LEAF gathering! :)
 
I will bring the firmware update ability to the next Gathering in Santa Ana,
one week from this coming Saturday.

On request, I can bring the update to other Gatherings as well.

However, it would be nice to see you again.
 
Future Firmware For the GID-Meter.

1. Presently version F1.09 is the latest firmware version, which added the
displaying of the "real SOC" percentage along with the raw GIDs, and the
percentage GIDs (a percentage of 281 raw GIDs).

Although the SOC value is, by itself, of little value in driving,
it is apparently of some interest to some people.

2. Presently the One-CAN Logging feature (EV or CAR) captures
enough of the CAN Messages to be very useful to most users.
However, the CAN library and our use of it tends to miss the
messages that arrive right after a preceeding message.

We have discovered the problem and are working on fixing
the library, and using it differently. Tests have been successful,
and I need to apply the techniques to the GID-Meter firmware.

I intend to do that in the near-term future.

3. Presently, the GID-Meter does not Write to the CAN bus, but
recent experiments in Writing Requests (for Request-Only
information) have demonstrated the (apparently reliable)
ability to Request and read the 4 Battery Pack temperatures,
the 96 cell-pair voltages, and what appears to be a measure
of the Pack's Capacity.

So, doing modifications to the CAN library and our GID-Meter
firmware (and closing the enable-writing hardware "jumper"
with a solder-blob) would allow us to show these helpful values.

I intend (not promise) to get this Request firmware working,
as an optional update to the GID-Meter.

See the next post for ideas on when and how often we might
Request the information, and how I might display the information.
 
Possible (not promised) new GID-Meter modes:

For greater safety, these Requests might initially be done
only on demand, when the user responds to a prompt.

For example, entering the 4-temperature mode (4), the
display might show "4C_?", and only Request and show
the 4 temperatures with after a press of the black button.

-------
Mode 4: Pack Temperatures

From the 4 temperatures, we could display the
Average, the High, and the Low, or
all 4 temperatures,
and possibly support a Degrees C or F option.

Initially, the 4 temperatures as "Cnn.n"
would probably be the choice.

If there is a degrees F option, the display
would show, for example, "124.6" in Arizona. :lol:

--------
Mode 5: Pack Capacity

Since one would rarely look at this very slowly changing
value, the Request might be "CAP?" and a typical display
might be "67.34" for a new, properly-calibrated 2013 LEAF.

Not knowing how or when, or if this value is calibrated,
and realizing that the calibration might be different from
one vehicle to another, we would probably choose to
display the "raw" value, and NOT say that it looks like
it could be Amp-Hours (Ah).

--------
Mode 6: Cell Pair Voltages

Although the data for all 96 cell-pairs is available,
just showing the spread in milli-volts (mv) as "-nnn"
and the Max, Ave, and Min voltage values in volts,
typically as "3.891" might be sufficient for most users.

The spread is an indication of how well equalized the
Pack is, with "-018" mv being a typical good number.

The actual voltages are less significant unless the
Min is less than ( Ave - 1.5 * (Max - Ave)), in which case
it is considered a low-side "extremist". If this condition
occurs at a low Pack charge level, the "extreme" cell
MIGHT be a candidate for closer inspection, if the
Pack is well equalized, I suspect.

more later...
 
Still to be discovered:

The 4 tire pressures.
The 12v Battery Voltage.

--------
What "Capacity" value indicates a 100% battery Pack?

From the data we are seeing, something around 66 to 67
seems likely for a typical Pack.

Certainly some Packs will have one cell-pair with a slightly
lower capacity, and that module would usually fill sooner,
and discharge faster than the other higher-capacity
cell-pairs, and thus limiting the Pack's usable capacity.
 
Gary, it would be great to have a real battery temp gauge in the LEAF. Keep us updated on your progress.

My personal preference would be to just average the 4 temps and display it in F. That way it would be easy to compare to outside air temp and the temp displayed on the dash.

Temps are pretty mild right now, but I worry about the pack overheating during the summer months.

Looks like you and TickTock have been pretty busy on the Canary project. Maybe one of you can offer a kit for that some day. Keep up the good work.
 
I am working on a new firmware upgrade for the GID-Meter.

1. Display Tire Pressures, when valid, in psi as "A39.2" or something
similar (when switched to the CAR-CAN bus). When switched to the
EV bus, the "invalid" indication will probably be " -- ", or some such.

The four different tires might be prefixed with A, C, E, F, or E, F, H, L.
Within the constraints of needing 3 digits for the data, and
having only one 7-Segment display digit left, there are a few other
possibilities, but apparently the Front/Rear and Left/Right
status is not included.

2. While reading the CAR-CAN bus, use the GIDs from
that bus to update the GIDs and %GIDs.

Note: This CAR-CAN bus GIDs seems the be available
when driving, but not when charging.

3. Add a function to select 10 intensity levels for the LED display,
and remember the setting in the internal EEPROM. Then,
the "bright" display can be dimmed for better pictures,
or for better night time use.

This feature will allow the "new" (almost compatible) SparkFun
LED display board to be used in the existing device, without
requiring a separate firmware version.

----------
I will post the new version, F1.10 as soon as I have tested it
sufficiently well, hopefully within this next week.

If you can write the new firmware into the AVR-CAN board's
JTAG programming port, and want to help test this version,
I could email the "H1.10" version to you if you PM me.
 
Nice to see this box is still being kept up-to-date. Gary, do you intend to keep the SOC meter as a passive (listen-only) device? If so, I would suggest adding the 5B3:D2 SOH data. Also, this can be easily converted to AHr (multiply by 65.5/100).
 
It may be too late to add, but if you have memory available the ability to default to the last used mode when it starts up would be a mean a lot less frustrating clicking at start up ;)

In my case it's probably not too relevant because I suspect I need dedicated hardware to update firmware
 
I will try to add the Start-Mode feature.

A programmer for $10 listed on EBay might work :
http://www.ebay.com/itm/Mini-USB-AVR-JTAG-Programmer-Debugger-for-AVR-ATMEGA-/290557303278" onclick="window.open(this.href);return false;
 
GID-Meter users,
I think I have finished the Firmware version F1.10 for the GID-Meter.
Briefly tested, but, of course, more testing would be good.

Perhaps there are others who can easily update and test it further?

With a bit more testing, I will post the HEX file and use it
as the standard firmware version.

There is a new Brightness (setting) Mode (Mode 4).
You change Modes with the Red button.
It allows setting the brightness for both the original and the
"replacement" version of LED from SparkFun.
Select brightness level with the Black button.
There are 10 different levels, 0 through 9, and half will be too dark
to be useful with each LED version.
Whatever brightness you have selected when leaving
the Brightness Mode (with the red button), if changed,
is remembered in the EPROM to be used on the next startup.

Folks with the original LED will usually see their display only
VERY dimly when they first start after a firmware upload.
Since the GID-Meter starts in Mode 1, three presses of the Red button
gets you to Mode 4, and 5 presses of the Black button should get you
to a "full ON" (or noticably brighter) setting.

Mode 5 allows seeing the 4 tire pressures, but you need to have
the CAR CAN bus selected (Bus Selector switch down is EV, up is CAR).
A "_._" indication says that the data is not available or the car indicates
that the data is invalid.

Who wants to help test?
Cheers, Gary
 
I will. Is there a link to the new firmware so I can flash it or wait until Saturday?
garygid said:
GID-Meter users,
I think I have finished the Firmware version F1.10 for the GID-Meter.
Briefly tested, but, of course, more testing would be good.

Who wants to help test?
Cheers, Gary
 
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