How to use stm32cubemonitor to observer 64bit length variable ?

yang2 · ‎2024-11-18

Dear All,

I want to use STM32CubeMonitor to monitor 64-bit variables, such as int64_t or uint64_t. However, it seems that 64-bit variables cannot be selected from the variable list (they are not displayed).

Is there any way to achieve this?

Best Regards,

Fan

stephane.legargeant · ‎2024-11-19

Hello

The 64bit format is not supported in STM32CubeMonitor because the data between nodes are transmitted in javascript "number" format. This format is used for the payload between node, in the processing and in the charts. It is a Double-precision floating-point format IEEE 754, and this format can not handle accurately int64. The IEEE number format as only 52 bits for the value.

For applications which are not using the full range or if you don't need perfect accuracy, it should be possible to read both 32bits parts and combine it in post processing. Nevertheless, if the acquisition is done when the value is changed there is a risk of misalignment between the low part and high part.

Best regards

Stephane

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stephane.legargeant · ‎2024-11-19

Hello

The 64bit format is not supported in STM32CubeMonitor because the data between nodes are transmitted in javascript "number" format. This format is used for the payload between node, in the processing and in the charts. It is a Double-precision floating-point format IEEE 754, and this format can not handle accurately int64. The IEEE number format as only 52 bits for the value.

For applications which are not using the full range or if you don't need perfect accuracy, it should be possible to read both 32bits parts and combine it in post processing. Nevertheless, if the acquisition is done when the value is changed there is a risk of misalignment between the low part and high part.

Best regards

Stephane