Compiler/MSP430FR5994: Array Indexing not Working Properly when Using Restricted Data Model

Caleb Overbay

Part Number: MSP430FR5994
Other Parts Discussed in Thread: BOOSTXL-AUDIO

Tool/software: TI C/C++ Compiler

Hi,

I've been fixing some bugs with the BOOSTXL-AUDIO Record Playback example and noticed some unexpected behavior when modifying the "data model" parameters. This project records audio data and stores it into two 64kB arrays placed in a custom data section that starts at the beginning of FRAM2 (0x10000). When the data model is set to "restricted", the audio data plays back in non-sequential order. However, when the data model is set to "large", the audio plays back just fine.

I read into the restricted data model and saw that individual objects are limited to 64kB in size. With this stipulation, the audio data should still playback correctly. However, I decided to halve the array sizes so that each is 32kB in size and the audio started to playback correctly. Can you shed some light on what could be causing the incorrect audio playback when switching between the different data models?

I've attached a zipped version of the project that is working correctly using the large data model. To experience the issue, you can simply change to the restricted data model and observe incorrect playback. The arrays in question are located in the audio_collect.c file and the playback of these arrays is located in the audio_playback.c file.

BOOSTXL-AUDIO_Record_Playback.zip

Best regards,

Caleb Overbay

over 7 years ago

0 Chester Gillon over 7 years ago

Guru 92251 points

Caleb Overbay said:
However, when the data model is set to "large", the audio plays back just fine.
I read into the restricted data model and saw that individual objects are limited to 64kB in size. With this stipulation, the audio data should still playback correctly. However, I decided to halve the array sizes so that each is 32kB in size and the audio started to playback correctly.

The attached project uses the TI MSP430 v16.9.4.LTS compiler.

I haven't looked at the generated code for the project, but based upon the description of the problem you may be encountering bug CODEGEN-1995 "Pointer math addend incorrectly truncated to ptrdiff_t on MSP430", or maybe CODEGEN-1412.

CODEGEN-1995 is reported as fixed in MSP430_16.9.6.LTS or MSP430_17.9.0.STS, so upgrading the compiler may fix the problem.

See Compiler/MSP430F5338: Adding offsets larger than 32k to pointers in restricted data model. for some background information on the bugs.

0 Caleb Overbay over 7 years ago in reply to Chester Gillon

TI__Genius 15370 points

Hi Chester,

Thanks for your reply. I can't seem to find the 16.9.6 or 17.9.0 compiler versions. After performing an update to CCS and manually downloading the latest TI MSP430 Compiler it doesn't seem to show in CCS. Have these versions been released yet?

Best regards,
Caleb Overbay

0 Chester Gillon over 7 years ago in reply to Caleb Overbay

Guru 92251 points

Caleb Overbay said:
I can't seem to find the 16.9.6 or 17.9.0 compiler versions. After performing an update to CCS and manually downloading the latest TI MSP430 Compiler it doesn't seem to show in CCS. Have these versions been released yet?

The CCS 7.2 Help -> Install New Software is showing that 17.9.0 is available for installation, but no sign of 16.9.6: