RC Model Reviews

I've now gotten the Android FrSky Dashboard to a state where i found it good enough to go onto the Android market.

It supports monitoring the Analog channels as well as RSSI. Setting units and conversion factors on these channels, and having the values read to you as you are flying.

It also supports setting the internal FrSky alarms.

It uses bluetooth, so it needs a rs232<->bluetooth bridge attached to the Tx module. (Regarding bluetooth causing interference with the radio transmission, I use it with two planes and a helicopter, and have never seen it affect the radio transmission at all..)

Market: https://market.android.com/details?id=b ... .frskydash
Webpage: http://projects.onomato.biz/projects/android-dash

Impressive!
So I went to check out your documentation and there doesn't seem to be a wiring diagram anywhere.
That and the "bridge" is covered in tape in your photo, bt_rear.jpg

Are you using it as a USART , a level converter, or both?
(the documentation for the ebay auction is pretty bad too, but it looks like a Max3225 level converter and Motorola HC05 microprocessor)

nevermind, downloaded the spec sheet from Frsky and I see that the USART is not required, just a level converter if the BT module will not accept 3.3V 9600Baud 8N1 and the Frysky Protocol sheet includes a schematic for a level shifter

http://www.frsky-rc.com/ShowProducts.asp?id=35
then click on the download button

bluetooth module:
http://kcwirefree.com/docs/KC21_Datasheet.pdf

I am not sure you need the Max3225 level shifter since both the Frysky module and Bluetooth module talk at 3.3V

By the way I bought the same bluetooth module for an arduino board, they are sold by dealextreme

http://www.dealextreme.com/p/wireless-b ... dule-80711
$6.60 US shipped

More info on using the BT module: http://elasticsheep.com/

Thanks!

I see that I need to add some more BT information on my webpage

I decided to get the BT module with a level converter, as I was fairly sure the DFT uses RS232 Level. (From Telemetry Protocol Document)

2.1. Host end
Serial COM RS232 level, setting: 9600bps, 8bit, No parity, 1 stopping bit.

I think the Schematic for level shifter in the same document, is the one used to provide RS232 level on the Rx, not on the Tx (Rx Serialport is oneway only, while Tx serialport is two ways?).

It might be that one can get the DFT to work directly with TTL, but my experiences with this is limited, so I though it best to play it safe. A TTL only BT module is much cheaper, so if it is possible to hook a TTL BT module directly to the DFT, that would be a cheaper and simpler option.

I use the "RS232 adapter" for one more thing though. When I do initial setup of the BT module (name only i think), I use the serial side, connected to a computer, to perform this setup. It might be that my USB<->RS232 cable supports TTL as well though. I have not tried this. It might also be that it is possible to program the BT module from the BT side, however, I did not get this to work.

Much of what I have done might not be the optimal way to do this, as my electronics skills are fairly limited, also the chinglish in the FrSky documentation does not always help

I will try to update Bluetooth documentation on my project page though.

In the strictest sense, RS232c uses ±12Volts, some companies use TTL levels +5V to zero, and some companies use 3.3V to zero.

I think both the BT and the Frysky modules use 3.3V

Frsky Telemetry Pins:
Port 1: 0~3.3V voltage, value: 0x00~0xff.
Port 2: 0~3.3V voltage, value: 0x00~0xff.
Port 3: COM port RX pin, RS232 level.
Serial COM setting: 9600bps, 8bit, No parity, 1 stopping bit.

I think they mean stop bit, not stopping, so the extremely standard 9600 8N1

I am not referring to the COM settings, but to the "RS232 level" part. (Port 3 in the quote above)
Internally in the module i am sure they use 3.3 or 5V, but exposed on pins, i still believe they use rs232 level.

I have not looked at it on a scope though to measure the actual levels though.

Takilara can you help me out a bit. With which frsky modules is the hardware and software of android dashboard compatible?

msev wrote:Takilara can you help me out a bit. With which frsky modules is the hardware and software of android dashboard compatible?

It is compatible with all the tx modules and receivers in the two way series from http://www.frsky-rc.com/Products.asp?BigClassID=17

It only supports the two analog though, so the hub currently does not add additional channels in the dashboard

Note that my wiring 'instructions' is for the DFT upside down, and probably be reversed for the DJT or DFR in a Futaba radio