File format:Stf

stf

Name	Sigma Test File
Status	supported
Source code (in)	stf.c
Source code (out)	—
Common extension(s)	.stf
MIME type	—
ASCII format	no
Compression	yes (LZO1X for Sigma, ZIP deflate for Omega)
Website	asix.net

The STF (Sigma Test File) format is the native file format of the Asix Sigma/Omega vendor software. Asix published an application note which describes the file format.

Format

See the SIGMAP01 application note for a description of the file content, and vendor provided examples.

Properties

"Sigma Test Files" contain a capture including its configuration and the sample data in a single file. Sigma software versions use a plain binary file, Omega software keeps several members in one ZIP archive. The file can be considered to have three parts: A magic marker for reliable file format detection, a header holding the settings, and the data part which holds the sample data. For more details see the application note.

Implementation

Import of *.stf files is planned, so that files which were captured with the vendor's software can get postprocessed with sigrok. Exporting *.stf files from sigrok is not planned.

The current implementation can read Sigma files in the 50/100/200MHz variants. Omega support depends on ZIP archive handling in sigrok input modules, which currently is not available in mainline sigrok. Future extension of the input module's feature set remains transparent to users.

See the input module's properties. Specification of the samplerate is only necessary when the file content either lacks the information or when a different value should be used, users can override file content with that option.

 $ sigrok-cli -I stf --show
 ID: stf
 Name: STF
 Description: Sigma Test File (Asix Sigma/Omega)
 Options:
   samplerate: The input data's sample rate in Hz. No default value. (default 0)

Inspect an .stf file's properties, use the input file for interactive exploration, etc. Automatic file type detection should make a user provided selection unnecessary in typical cases.

 $ sigrok-cli -i ex_sigma_uart.stf --show
 Samplerate: 50000000
 Channels: 1
 - Input12: logic
 Logic unitsize: 1
 Logic sample count: 3649289

 $ sigrok-cli -i ex_sigma_usb_incl_lic.stf --show
 Samplerate: 200000000
 Channels: 4
 - Input1: logic
 - Input2: logic
 - Input3: logic
 - Input4: logic
 Logic unitsize: 1
 Logic sample count: 411750492

 $ sigrok-cli -i ex_sigma_disp.stf --show
 Samplerate: 50000000
 Channels: 13
 - D0: logic
 - D1: logic
 - D2: logic
 - D3: logic
 - D4: logic
 - D5: logic
 - D6: logic
 - D7: logic
 - -RST: logic
 - -CE: logic
 - -RD: logic
 - -WR: logic
 - C/D: logic
 Logic unitsize: 2
 Logic sample count: 169059308
 Trigger count: 1

 $ pulseview -D -i ex_sigma_usb_incl_lic.stf &

Screenshots

UART capture visualized

USB capture visualized

Resources

• SIGMAP01 application note
• vendor provided examples