Here is a little more detail about the current product and installation.
A complete WattsLeft™ consists of the Display/Electronics unit, the rotary Selector and OBCII right angle connector with one long cable going to the Display and a shorter cable going to the selector. The long cable is about 6’ 10” and the short cable is about 3’ 1”. Starting raw cable lengths are 7’ and 3.5’ before being attached at both ends.
If necessary for installation (advanced type) the Display/Electronics unit can be disconnected from the cable by removing the cable clamp screw and carefully removing the eight pin connector. The orange Power wire is always closest to the side edge. Don’t get that wrong or you will drive +12 volts into the CAN transceiver and load the Car EV CAN down trying to run the electronics/display!
In this backside shot you can see the reset button just below the black 8 pin connector. When you have the Bluetooth module the outer plastic ring will pulse pink when looking for a connection and will stay solid pink when a connection is made. This will happen independent of whether any EV data is being sent.
Here are some pictures of the first customer install. The simplest install is to put the unit in the center of the dash above the Navigation screen and angled towards the driver. The wire runs down the left side of the center black control panel.
Here is an overview shot.
Close-up of display unit.
Close-up of selector unit. Note cable still needs to be moved to the right and should follow the seam on down.
Close-up of underside of dash. Note that the cables from the OBDII connector are routed inside the removable panel to keep them clear of the driver’s feet. There is also sufficient slack in the OBDII cable to allow it to be unplugged without the need to remove the lower panel again. Nissan will need access to the OBDII connector to do any service so it is a good idea to unplug it before going in. Note unplugging the connector will power down WattsLeft™ and all History data will be LOST! So write it down before unplugging.
A more advanced installation would pull the center dash unit out (with Nav screen) so the cable can be route directly down so it does not show. A small amount of filing may be needed on the gray plastic lip so the cable does not get pinched or block the center dash unit from being pushed back in place.
Here is a close-up of the top side of the electronics board. Note that this board has two CAN transceivers for testing but the shipped board will only have one installed (EV CAN). There is currently no firmware to support the Car CAN bus.
Now the back side without the Bluetooth module installed.
Here it is with the Bluetooth module installed.
Set of completed boards with display units attached ready to be install in cases.
Here are the eight completed assemblies. Note that only three have LEDs installed the other five will get LEDs when they are installed in the cases.
Now for Gary’s questions:
The current product only supports logging EV activity over Bluetooth. However when Bluetooth is not installed different firmware is install to support a hardwired serial port. If you look closely at the back of the board just below the top left corner hex plastic standoff and above the black Bluetooth connector you can see two pins. Top one is ground and lower one is serial data. Just connect it to a DB9 to get a hardwired serial port. But I recommend spending the extra $20 and getting Bluetooth as you avoid the cables and connectors. The polarity of the serial data is opposite between hardwire and Bluetooth so different firmware is needed.
Yes the Bluetooth shows up as a virtual Comm Port on the PC. I have used it with the CAN-DO program to log EV data. Baud rate is 57,600. I send two extra bytes at the end which are the original CRC data and ignored by CAN-DO. It would be nice if CAN-DO had an option to accept only CRC validated data. But the first few bytes of the CAN-DO format need to be rearranged inside the PC to match the original CAN format for the CRC to match.
The format I send is 13 bytes (CAN-DO is 11 bytes). First 11 bytes are the same as CAN-DO so you can use Gary’s program. Format is: SYNC, MM, NH, Data 0 thru Data 7 followed by two bytes of original CRC. For the CRC to match the MM, NH bytes need to be rearranged back into the original three bytes send from the EV CAN bus (0H, MM, 0N). The ID data is represented as HMM and N refers to the data count. Note that only eight byte data frames are passed thru so N always equals 8. SYNC= 0x53 xor MM xor NH.
My PC has Bluetooth installed so no dongle. I would think any dongle should work as this is basic serial.
As shown in earlier pictures the LCD is Blue with White characters. I have found that if I leave the protective film they ship with it ON it acts as a ¼ retarder and allows the display to be view with polarized glasses. Since this was not the intended purpose of the film the manufacturer just slapped it on so small bubbles are unavoidable in the finished product. I don’t see them when the display is ON but if they bother you you can always remove the film.
I think that takes care of all the current questions.
I am currently working on a small firmware updated to allow better control of the LED by disabling it on certain screens. The change will allow it to function only on the 1st screen (SOC) and the 5th screen (DTE-V) and 6th screen (DTE-T).