UART Protocol Analysis

Example: measure a UART protocol with the features below:

Baud Rate: 9600; Data Bit:8; Stop Bit:1; odd parity check provided; sending A~P to LCD screen.

Step 1: Double click icon of LAP-32128U-A_STD to run the software

Step 2: Click “OK” to load the last file used or click “Cancel” to create a new file capturing data from the window of Logic Analyzer appears.

Step 3: When software interface appears, please follow setup process below:

1.      Go to setup “RAM size” which 2K、16K、32K、64K、128K are provided. User could select the RAM size meeting requirement. We are selecting 2K here.

2.      Go to setup suitable “sample rate” which should be setup at least four times higher then the Baud rate of the device under test. In this case, we select 100KHz to be the frequency.

3.  Go to setup trigger position at 0%.

Step 4: Go to click channel setup  icon, the window of channels setup will appear. Please follow the processes below to setup and rename the channels.

1.        Go to click “Delete All” to clearing up all channels.

2.        Go to click “Add Bus/Signal” getting “New0”channel.

3.        Highlight “Port A0” to set “New0” cannel.

4.        Go to re-name “New0” into “Tx”.

Step 5: Go to setup the trigger condition as either edge for the UART signal.

Step 6: Go to click the Single Run   icon to turn on the logic analyzer capturing the data, then turn on the tested device. The logic analyzer is going to capture and calculate signals. As soon as the data has been stored in RAM, then system displays the wave.

Step 7: When the system completes the wave display, then go to click   to show all data which is displayed at better way to be looked.

Step 8: Go to click the UART  icon, the window of SPECIAL BUS UART SETUP is displayed to setup UART conditions.

1.      Go to click off the “Rx” function.

2.      Go to Bus Property to click pull down menu of “Data Direction” selecting “LSBà MSB” for this case.

3.      Go to Bus Property to click on the “Use the reverse data level for decoding”

4.      Go to Bus Property to click pull down menu of “Parity” selecting “Odd parity” for this case.

5.      Go to Bus Property to click pull down menu of “Baud Rate” selecting “9600” for this case.

6.      Go to Bus Property to click pull down menu of “Data Bit” selecting “8” for this case.

7.      Go to Bus Property to click pull down menu of “Stop Bit” selecting “1” for this case.

8.      Go to UART Bus text to click ASCII as data format for this case.

9.      Go to click “start” then click “OK” to decode I²C protocol, when all conditions are set.

Step 9: Go to click Zoom in  icon, the adjust the wave into the better ratio to view.

Step 10: Go to click the roll to shift and view the wave.