Re: BlueSaab v5.0 released!

Posted by sbt on Nov 09, 2016; 5:14am
URL: http://bluesaab-forum.90.s1.nabble.com/BlueSaab-v5-0-released-tp700p759.html

Seth,

Great job on this. Just built v5.0 and it works! I will go the amp module since the volume's a bit low, but otherwise good.

I ordered the BoM before you revised the LED resistors, but there were enough spare 10ks to replace all except R16, which is fine with 2.2k and the originally spec'd green LED.

Couple of errata for the current BoM:

* The "Customer Part No" for the first item, "Thick Film Resistors - SMD 1/8watts 10Kohms 1%" includes R13, but this is a 20k resistor on schematics, and is included as item 6 on the BoM. Gave me an extra spare 10k for R17 though, so.

* The CPN for the third item "Multilayer Ceramic Capacitors MLCC - SMD/SMT 50volts 0.1uF X7R 10%" has "C5" instead of "C3".

* The CPN for the 19th item "Multilayer Ceramic Capacitors MLCC - SMD/SMT 50volts 10000pF X7R 10%" now includes C23, but v5.0 doesn't have this component?

* It looks like the part number for the Mini USB socket "RN52_FIRMWARE" has changed.

Building:

* The specified ATMEGA328P doesn't ship with a boot loader. That's fine, but it's handy to know this as this is the first thing needed to upload before uploading the SAAB-CDC software and the UPLOAD USB socket can't be used for this part; another arduino (using the ISP1 header) or FTDI interface (using the six pin header below the ATMEGA328P) is needed. EDIT: Incorrect in terms of FTDI; according to Seth, only ISP1 can load the bootloader.

* The mic socket has location bumps on the base, but there are no holes in the PCB (as for the RN52_Firmware socket). I just cut them off the socket, but it would be nice to have them to locate the socket precisely on the board. I see that in the current layout, that's not possible due to the location of the BT module.

* I used solder paste and "skillet reflow" to do the surface mount components on the top of the board. This was a time saver and the quality is better than hand soldering. This included the reset button and mic socket. I then hand soldered the bottom side surface mount components. It's important to precisely place the fine pitched BT module and FT interface chip before drag soldering (which I think is the best approach). I tacked the corners with small amounts of paste and checked precise alignment before applying paste to the rest of the pins.

* Lastly, I added all the through hole components (headers/sockets/connectors). I only populated the ISP1 header, as I wasn't using the FTDI (the six pin header below the ATMEGA328P) option. Either one of the other is needed depending on whether an FTDI programmer or ICSP (another arduino, e.g.) is used to load the bootloader.

* The RN52_FIRMWARE socket and UART header don't need to be populated, if everything works. Once the bootloader is installed, all the programming can be done via UPLOAD.

EDIT: For this version, follow the steps from 13 on the RN52 configuration tutorial, after connecting via the USB port BEFORE loading the SAAB-CDC software. This sets the RN52 correctly.

Testing:

* When the board is plugged in via ISP1 or UPLOAD, the Power LED should turn on.
* When uploading the code, the RXLED and TXLEDs should blink.
* When the software's been uploaded, the BT1 and BT2 LEDs should flash alternately, signalling the BT module is ready to pair.
* When connected to the car, one of the CAN LEDs should glow faintly (it's really blinking rapidly) as well, this signals there is traffic on the I-BUS.

* Once a phone is paired, switching on the radio the SID should chime. Once the CDC source is selected, the module will pair to the phone. Another softer beep should come through the speakers to signal pairing. EDIT: This pairing sound won't happen once the RN52 configuration is done; these sounds are disabled. I've noticed that playback starts and stops automatically with IHU on/off, which is nice.

* Without an amp module, the volume is low at default levels for IHU/phone. If things seem to be working, e.g. the phone's playing music, the SID indicates "CD PLAY 01", but no sound, try turning up the volume on the IHU and your phone. EDIT: Again, by default the RN52 module volume is low. The RN52 configuration process should ameliorate this a bit.

Cheers,
Sam.