Created attachment 534 [details]
PulseView image of UART decode error where data source is set to memory

Environment.
Using Pulseview AppImage downloaded 3 August 2019.
Linux Mint Mate 18.3 x86_64 (Ubuntu 16.04 base)
Capturing device Rigol DS1102E digital oscilloscope connected via USB.
Datasource is ascii characters transmitted signal over TTL UART, monitored via oscilloscope probe channel 1.

Symptoms.
When viewing pulse data that is captured in memory on a DS1102E, the signal pulses are correctly converted and displayed as pulses along with the DS1102E sample points. The UART decode displays an error "Decoder reported an error".
Pulseview setting:
  Data source: Memory
  Timebase: 1ms
  Trigger source: CH1
  Trigger slope: f

This UART ascii decode error does not occur when the "Data source" is set to "Live".

Pulseview logging has the following information.
pv: "Querying config key samplerate resulted in not applicable" 
"UART": Error cleared
"UART": "Decoder reported an error"
SamplerateError: Protocol decoder instance uart-1: : Cannot decode without samplerate.
Traceback (most recent call last): File "/tmp/.mount_PulseV9gVeTt/usr/share/libsigrokdecode/decoders/uart/pd.py", line 428, in decode raise SamplerateError('Cannot decode without samplerate.') uart.pd.SamplerateError: Cannot decode without samplerate. 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 

I have pasted the full log output at the end of this message.

Also attached is the following image.
Pulseview_trace_data_source_memory.png - image of displayed trace with error where data source setting is memory.


The reason I am using the memory capture is that the live capture only displays the active trace frame displayed on the DS1102E, and not the additional frames that are available for live view. This limits that amount of displayed decode data in PulseView. This seems to be remedied by recording multiple frames in the DS1102E memory and viewing this memory using PulseView to decode the data. Unfortunately the data decodes are not working as the sample rate is not known with the PulseView data source set to memory.

I did a search in sigrok-devel archives and bugtrack but did not find this reported.

Regards
Michael

pv: "UART": "No input data"
sr: hwdriver: Cannot set 'samplerate' to 0.
pv: "Failed to configure samplerate:" invalid argument 
"UART": Error cleared
pv: "Querying config key samplerate resulted in not applicable" 
pv: "UART": "No input data"
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
"UART": Error cleared
pv: "Querying config key samplerate resulted in not applicable" 
"UART": "Decoder reported an error"
SamplerateError: Protocol decoder instance uart-1: : Cannot decode without samplerate.
Traceback (most recent call last): File "/tmp/.mount_PulseV9gVeTt/usr/share/libsigrokdecode/decoders/uart/pd.py", line 428, in decode raise SamplerateError('Cannot decode without samplerate.') uart.pd.SamplerateError: Cannot decode without samplerate. 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
"UART": Error cleared
"UART": "Decoder reported an error"
SamplerateError: Protocol decoder instance uart-1: : Cannot decode without samplerate.
Traceback (most recent call last): File "/tmp/.mount_PulseV9gVeTt/usr/share/libsigrokdecode/decoders/uart/pd.py", line 428, in decode raise SamplerateError('Cannot decode without samplerate.') uart.pd.SamplerateError: Cannot decode without samplerate. 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
"UART": Error cleared
"UART": "Decoder reported an error"
SamplerateError: Protocol decoder instance uart-1: : Cannot decode without samplerate.
Traceback (most recent call last): File "/tmp/.mount_PulseV9gVeTt/usr/share/libsigrokdecode/decoders/uart/pd.py", line 428, in decode raise SamplerateError('Cannot decode without samplerate.') uart.pd.SamplerateError: Cannot decode without samplerate. 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: Acquisition took 4.74 s
"UART": Error cleared
pv: "Querying config key samplerate resulted in not applicable" 
pv: "UART": "No input data"
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
"UART": Error cleared
pv: "Querying config key samplerate resulted in not applicable" 
SamplerateError: Protocol decoder instance uart-1: : Cannot decode without samplerate.
"UART": "Decoder reported an error"
Traceback (most recent call last): File "/tmp/.mount_PulseV9gVeTt/usr/share/libsigrokdecode/decoders/uart/pd.py", line 428, in decode raise SamplerateError('Cannot decode without samplerate.') uart.pd.SamplerateError: Cannot decode without samplerate. 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
"UART": Error cleared
"UART": "Decoder reported an error"
SamplerateError: Protocol decoder instance uart-1: : Cannot decode without samplerate.
Traceback (most recent call last): File "/tmp/.mount_PulseV9gVeTt/usr/share/libsigrokdecode/decoders/uart/pd.py", line 428, in decode raise SamplerateError('Cannot decode without samplerate.') uart.pd.SamplerateError: Cannot decode without samplerate. 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: "Querying config key samplerate resulted in not applicable" 
pv: Acquisition took 2.29 s