Template application should be simple(r)

[WillBellido]

Hi,

the template application hides SDS simplicity and creates confusion for the first time user. My observations:

1. #ifdef SDS_PLAY duplication is confusing and overwhelming:

• Combine sds_play_buf_data_in and sds_rec_buf_data_in. Both are used for the exact same purpose: to hold the input data for the algorithm.
• Similar with playIdDataInput and recIdDataInput. Both serve the same purpose, handle for input data to the algorithm.
• printf statements under #ifdef SDS_PLAY just bloat the overview. Examples are printf statements on:
  • Stream open success
  • Stream open failure
  • Stream close success
  • Stream close failure

2. Variable playTimestamp creates a hidden cross-file dependency via global variable

3. Don't prefix everything with SDS

• Names like

  • sds_algorithm_config.h
  • sds_algorithm_user.h
    trigger questions: What is an SDS algorithm? How do I need to configure SDS algorithm? Just use user_algorithm.c

• Define SDS_ALGO_DATA_IN_BLOCK_SIZE configures block size for the AI/ML model not for SDS algorithm (misleading).

• What about "Configure the input data block size (SDS_ALGO_DATA_IN_BLOCK_SIZE) for the algorithm under test and remove this line."
  instead of "Configure algorithm under test input data block size (SDS_ALGO_DATA_IN_BLOCK_SIZE) for your algorithm and remove this line!"

• Similar for sds_data_in_*.c, they serve to feed the AI/ML model not SDS.

4. Don't use to many files

• Why is app_main empty? Why do I need to search for the sdsControlThread? (breaks the flow)
• Why is OpenStreams/CloseStreams not in sds_control.c? (breaks the flow)

[ReinhardKeil]

5. Make stream names clearer.

• Currently DataTest and Algorithm use the same stream names. This is confusing when you start with SDS.
  • use for DataTest: TestInput, TestOutput
  • use for Algorithm: AlgoInput, AlgoOutput

There are also related *.sds.yml files which would make it then clearer how test files actually relate.

6. Simplify "sds_rec_play" to just "sds".

I suggest also to change:

• "sds_rec_play.h" -> "sds.h"
• "sdsRecPlayId_t" -> "sdsId_t".
• #define SDS_REC_PLAY_OK - SDS_OK

etc.

7. Simpler Control Interface

Today, the control interface uses a push button and two LEDs. Once #207 is implemented, the control interface in the template could be simpler:

• 'status_exchange' function that has a different implementation for HOST connection and FILE sytem:
  • HOST connection: Not push button only controlled via the HOST interface, error output only on HOST
  • FILE system: Push button (could have a different SDS, error output with printf
• Only one LED with 0.5Hz when not recording/idle 5Hz when recording.

8. Introduce SDS Version 3, currently developed in a different branch.

• clean up aggressively the source code
• try to merge sdsRecOpen/sdsPlayOpen into sdsOpen (with additional mode), sdsRecClose/sdsPlayClose into sdsClose
• playTimestamp and timestamp -> sdsTimeSlot that is set in sds_data_in_user.c / sds_data_in_play.c
• rename sdsRecPlay_t *rec_play = id; to sdsStream_t *stream = id;
  • https://github.com/ARM-software/SDS-Framework/blob/main/sds/source/sds_rec_play.c#L631