Linkit ONE

Hi guys i'm using a Linkit ONE board for my project and the last part that i need to do is send a CAN BUS message...now on this board i have already used the tx/rx for an rfid reader so i dont think i can use my CAN BUS module unless i'm wrong.

Would i be able to do something like use another board - say an UNO and send a signal from the Linkit ONE so that the UNO can send the CAN BUS message?

If no body knows about the Linkit ONE, how about the ability to link 2 boards together? Whats the usual route when you run out or hardware ports?

Does the Linkit ONE support I2C?

Or SPI?

I found this 'LinkIt ONE only support I2C master, not slave. '

I found this on SPI but don't know what it means : https://labs.mediatek.com/site/global/developer_tools/mediatek_linkit/api_references/Lib_SPI.gsp

I found a little spec sheet on the board but not sure what most of it means.

http://labs.mediatek.com/site/global/developer_tools/mediatek_linkit/hdk_intro/index.gsp

The processor supports both as indicated by the link you provided.

Find a CANBUS controller that works with I2C and/or SPI. Given the fact that Mediatek Labs provides an SPI library that seems like a good choice. You will have to give up four I/O pins to interface with the CANBUS controller.

Once you decide on a controller, find a breakout board with that chip. Something from Microchip is a good first choice.

Hi and thanks for your input so far, i already have the can module which is a https://www.sparkfun.com/products/10039 it does have SPI - i'm a bit out of my depth now.

Are you sugesting that i directly connect the Linkit ONE directly to the CAN BUS unit or plug the CAN BUS unit into an UNO and connect that way?

If it makes any difference i will just be sending CAN BUS signals and not reading them.

markmonkey: Are you sugesting that i directly connect the Linkit ONE directly to the CAN BUS unit...

The CANBUS controller will certainly work connected to your board.

I can't tell if anything else on that shield may cause a problem. I doubt it.

However, I have no idea if that shield can be directly connected to your board. Were I in your shoes I would first use jumper wires from one to the other (or ask the board manufacturer to confirm the shield will work) (or both). You will be connecting VCC, GND, CS (for the CANBUS controller), MOSI, MISO, and SCK. If you are especially paranoid, include series resistors on the signal lines (CS, MOSI, MISO, and SCK). Anything >= 165 ohms will help. Anything >= 3300 ohms should eliminate any possibility of damage. However, the higher the resistance the more likely you will encounter communications problems at high bit rates. Try to keep the jumper wires short.

If it makes any difference i will just be sending CAN BUS signals and not reading them.

No difference.

As always thank you for your reply, looks like i have a bit of reading to do to decipher your reply.

I have been doing some research and have a question before I continue.

I now know that my MOSI, MISO, SCK is pin 11, 12, 13 – I also notice that my can bus module is 11, 12, 13 so theoretically if I stacked the can bus on top of the Linkit the pins would match, so my question is I assume if I do this the can bus will use my pin 0, 1 which is what I need for my RFID reader so this would not be an option?

So I will need to have jumper wires going from 1 to the other which is fine.

So I think my final question is – once I have connected them both together with jumper wires do you have a code snippet to get me started with sending the can bus signal from the Linkit to the can bus module which will in turn push out to the car?

Many thanks you your help thus far.

my question is I assume if I do this the can bus will use my pin 0, 1 which is what I need for my RFID reader so this would not be an option?

No. The CANBUS controller only communicates via SPI (MOSI, MISO, SCK, CS).

As far as I can tell, the UART connection (pins 0 and 1) passes through to a header for a serial LCD display.

once I have connected them both together with jumper wires do you have a code snippet to get me started with sending the can bus signal from the Linkit to the can bus module which will in turn push out to the car?

I do not.