Skip to end of metadata
Go to start of metadata

You are viewing an old version of this page. View the current version.

Compare with Current View Page History

« Previous Version 6 Next »

This section refers to the following sample application(s):

  • 02-uart_raw

This application is new to OCSDK 1.2.0

In addition to the using the UART with hardware HDLC framing, the UART serial port can be used raw (not HDLC) encoded - this allows an external microcontroller or sensor with a UART interface to communicate with your application. 

Your application can set up the UART device to trigger a notification whenever valid bytes are received over the serial port.  Similarly, your application can send bytes over UART.  In raw mode, you can configure the baud rate, number of stop bits, parity, and inter-byte delay settings.

The 02-uart_raw Sample Application

The 02-uart_raw sample application creates two tasks, and defines three CLI commands - len(gth), delay, and tx. A companion Python script uart_raw_app.py runs on your computer and connects to the API UART port of your device.

Setup

To test bidirectional UART messaging:

  • Your computer and 

    SmartMesh mote

     are connected over a USB cable.
  • Your 

    SmartMesh mote

     is programmed with the 02_uart_raw sample application.
  • Your computer runs the following:
    • The uart_raw_app.py Python script (available in the 

      onchipsdk/

      src/

      /app/02-uart_raw/ directory).
    • A terminal client to enter CLI commands for the 

      SmartMesh mote

      .


You need to know the API and CLI serial ports corresponding to your

SmartMesh mote

. You will connect the uart_raw_app.py Python script to the API port, and the terminal client to the CLI port.

Refer to the SmartMesh IP Tools Guide for information about how to identify the different serial ports.

Overview

The 02-uart_raw sample application creates two tasks.

  • The uartTxTask task transmits a number of UART "packets" from your 

    SmartMesh mote

     to the uart_raw_app.py Python script. The number of packets to send, their length, and the inter-packet delay are set using CLI commands.
  • The uartRxTask task listens for incoming UART bytes, sent in this case by the the uart_raw_app.py Python script.
The 02-uart_raw sample application defines three CLI commands:
  • use len to specify the length, in bytes, of the packet the uartTxTask task transmits.
  • use delay to specify the duration, in ms, for the uartTxTask task to wait between two successive packets.
  • use tx to specify the number of packets to transmit, and trigger the uartTxTask task to start transmitting.
The uart_raw_app.py Python script connects to the API port of your 

SmartMesh mote

. It defines a number of commands allowing you to transmit UART frames to the 

SmartMesh mote

. It also prints the UART frames it receives. Start the uart_raw_app.py Python script by double-clicking on its file.


Before you run this application, make sure you have Python and pyserial installed on your computer.

Refer to the SmartMesh IP Tools Guide for installation instructions.

The uart_raw_app.py Python script defines the same CLI commands are the 02-uart_raw sample application, i.e. len, delay and tx. On top of those, the uart_raw_app.py Python script defines the connect command to connect it to the API serial port of your 

SmartMesh mote

.
You can type help on both the 02-uart_raw sample application and the uart_raw_app.py Python script to obtain the list of available commands.
Type help on the your 

SmartMesh mote

:


> uart_raw app, ver 1.2.0.1
SmartMeshIP stack, ver 1.4.0.5
> help
help <command>
Commands:
   mtrace
   mset
   mget
   mseti
   mgeti
   mxtal
   mfs
   mlog
   mtrace
   minfo
   mshow
   len
   delay
   tx
>

Type help in the uart_rawapp.py Python script:

uart_app OCFDK Sample application
> help
Commands:
   connect <comPort>
   baudrate <bps>
   stopbits <stopbits>
   len <numBytes>
   delay <numMs>
   tx <numPackets>
   exit
>

Send UART frames from the 

SmartMesh mote

First, connect the uart_raw_app.py Python script to the API port of your 

SmartMesh mote

 (here on COM28).

> connect COM28
>

On the 

SmartMesh mote

, type the following command to send 5 packets of 10 bytes each, with an inter-packet delay of 100 ms to the uart_raw_app.py Python script. 

> len 10
> delay 100
> tx 5
> Sending 5 UART packets, 10 bytes, delay 100 ms
uart TX ( 5): 00 01 02 03 04 05 06 07 08 09
uart TX ( 4): 00 01 02 03 04 05 06 07 08 09
uart TX ( 3): 00 01 02 03 04 05 06 07 08 09
uart TX ( 2): 00 01 02 03 04 05 06 07 08 09
uart TX ( 1): 00 01 02 03 04 05 06 07 08 09
done.

The following is printed by the uart_raw_app.py Python script.  Note that the uart_raw_app.py uses the 00 as a break between packets - there is no data framing in the raw UART (other than the interpacket delay).

uart RX: 00 01 02 03 04 05 06 07 08 09
uart RX: 00 01 02 03 04 05 06 07 08 09
uart RX: 00 01 02 03 04 05 06 07 08 09
uart RX: 00 01 02 03 04 05 06 07 08 09
uart RX: 00 01 02 03 04 05 06 07 08 09

Receive UART frames at the 

SmartMesh mote

On the uart_raw_app.py Python script, type the following command to send 5 packets of 10 bytes each, with an inter-packet delay of 100 ms to the 

SmartMesh mote

:

> len 10
> delay 100
> tx 5
Sending 5 UART packets, 10 bytes, delay 100 ms
uart TX (  5): 00 01 02 03 04 05 06 07 08 09
uart TX (  4): 00 01 02 03 04 05 06 07 08 09
uart TX (  3): 00 01 02 03 04 05 06 07 08 09
uart TX (  2): 00 01 02 03 04 05 06 07 08 09
uart TX (  1): 00 01 02 03 04 05 06 07 08 09
done.
>

The following is printed at the 

SmartMesh mote

:

uart RX (10 bytes) 00 01 02 03 04 05 06 07 08 09
uart RX (10 bytes) 00 01 02 03 04 05 06 07 08 09
uart RX (10 bytes) 00 01 02 03 04 05 06 07 08 09
uart RX (10 bytes) 00 01 02 03 04 05 06 07 08 09
uart RX (10 bytes) 00 01 02 03 04 05 06 07 08 09

The mote uses the inter-byte timeout provided in the dn_open() call to "frame" the incoming bytes.

  • No labels

Documentation

Questions

Issues

Source code