I got my 2206A just today and connected it to an Arduino.
I sent "Hello world!" to the console at different baud rates
and monitored the TX pin of the Arduino with the PicoScope.
Everthing was fine from 9600 to 38400 baud. With higher
baud rates it doesn't work.
Sorry to hear you are experiencing problems using the serial decoder. I have tested the serial decoder previously with 256 KBaud and a 2204A device; it is definitely capable of decoding such rates without any errors.
Can you send me a screen shot of your settings and then use the single shot trigger to capture one data frame (one character) for me. I will take a look at what may be causing the problem.
Bilal Patel
Technical Support Engineer
Pico Technology
Problem solved: The real baudrate of the Arduino is 58.824,
2,1% higher than 57.600. This is within the specifications.
And the PicoScope Software ist not very fault-tolerant.
In cases like this it would be a solution to increase the fault
tolerance or to open a dialog with the question:
"Real baudrate may be 58.824, shall I change the baudrate?"
As user I expect a higher fault tolerance at standard baud rates
and a smaller fault tolerance at custom baud rates. And/or
perhaps the option to choose a custom fault tolerance.
Good to know you found the issue. Depending on the system, even slight mismatches in the baud rate can cause issues. For example, when I design a UART receiver using the bit-bang method, I would design it such that it would read exactly at the middle of each bit so any minor fluctuations would not matter so long as it is within the bit rate. However if the receiver was designed to read towards the end of the bit, a slight mismatch in timing will create an error. Since there is no governing standard for UART, it isn't safe to be left to assumption.
You will experience issues if the wrong 'Collection Time' is set. The decoder requires sufficient data to be collected for it to display the correct result. e.g.
9600 baud = 104 us/bit
(start bit + 8 data bits): 104us x 9 = 936 us (0.936 ms)
Therefore a collection time near 1ms/div should be used.
I noticed your voltage threshold and hysteresis may have been set incorrectly. For a 5V signal I would suggest using a threshold of 3.7 V and a hysteresis of approximately 0.5 V. the software
Hope this information helps, if you experience any further problems, please feel free to let us know.
Bilal Patel
Technical Support Engineer
Pico Technology