Safe & Sound - Safety Jacket for the Tolling Industry #5: Writing your own protocol

RE: Safe & Sound - Safety Jacket for the Tolling Industry #5: Writing your own protocol

ipv1 — Wed, 22 Mar 2017 18:26:41 GMT

[mention:8fb233e8974445138ef0af2b63b49f94:e9ed411860ed4f2ba0265705b8793d05] sir,

As a generalisation the term protocol could be used for, "a set of rules that govern the successful communication between two or more entities using the same media". In this experiment, the ability to 'address' nodes has been introduced to facilitate communications just as in I2C or ModBUS. I hope to add another layer on to allow more functionality based on the same principles used in the design of TCP/IP and it should reinforce the information provided.

The Intel Galileo, Gen2, Edison do not have the a dedicated I2C Hardware block to by understanding. Their master functionality is executed in software in the drive layer of the Yocto Linux image and is more or less a bit bang scenario. The YUN with Linux is able to do I2C Slave since it uses an AVR and it's I2C peripheral. I am currently looking at alternative methods but it seems adding a small microcontroller such as an MSP430 in slave mode I2C and Slave more SPI would be a good solution. Its on my todo list for next week where an MSP430G2553 will be demonstrated as an I2C SPI bridge operating at 3.3V and 5V TTL. I made a PCB with the controller and Voltage level converter that I need to test but it will solve a number of problems in the future.

Thanks again for the inputs.

Cheers,

RE: Safe & Sound - Safety Jacket for the Tolling Industry #5: Writing your own protocol

mcb1 — Wed, 22 Mar 2017 10:15:57 GMT

Personally I don't tend to think of UART, SPI, I2C as a protocol.

IMO they are a transport mechanism or a means of sending the data.

Your code can be sent over any medium (SPI, I2C, Wireless, Ethernet) and as long as the far end can process it, then it can communicate.

Boards such as the Intel Galileo, Edison etc will not function as I2C slaves

I couldn't get the Edison to talk One Wire (using Arduino sketch), but I was able to make it drive the I2C display.

As I understand it is a timing issue, since it runs under the OS.

I haven't tried it as a slave, so maybe that should be an exercise for next week.

Cheers

Mark

RE: Safe & Sound - Safety Jacket for the Tolling Industry #5: Writing your own protocol

COMPACT — Fri, 17 Mar 2017 09:00:08 GMT

I see that you've got your Enumeration Gun out and are turning everything insignificant numbers!

Positive integers to be precise. [View:/resized-image/__size/16x16/__key/commentfiles/f7d226abd59f475c9d224a79e3f0ec07-59d75017-8293-44d7-918d-fad11d912493/contentimage_5F00_4027.png:16:16]