Tool/software:
We are new to TI's MSP430 family and have previously developed a flow meter using another company's IC. However, due to cost-cutting and the need for a single-chip solution, we have chosen the MSP430FR6043 for our new design.
Currently, we are testing the MSP430FR6047 EVM as part of our evaluation process. In our previous implementation, we used a threshold-based first-hit detection and flow algorithm, where we periodically validated and adjusted threshold levels to compensate for aging, sensor sedimentation, and other factors.
Given that ADC-Based Correlation is used in the MSP430FR6043, we would like to understand the following:
Threshold Adjustment – Do we need to implement a mechanism for periodic threshold validation and adjustment similar to our previous approach? If so, could you provide guidance on the recommended procedure?
Bubble Detection – How does TI’s solution eliminate or compensate for bubbles in the measurement process?
Your insights on these aspects would be highly valuable for our design considerations.
Looking forward to your response.
Hi,
1. For cost cutting I would suggest MSP430FR6007 for water meter application.
2. The algorithm are the same on FR6047/FR6043/FR6007. If you have already added a threshold-based first-hit detection and flow algorithm on the FR6047 platform. It would be easy for you to migrate the code on FR6007 platform.
3. Usually, we do not need to adjust the threshold. I think it is a nice to have for some special application. TI does not have a demo code to adjust the threshold.
4. Well, TI does not have algorithms to solve bubble issue.
Best regards,
Cash Hao
Dear Cash,
Thank you for your prompt response and valuable suggestions.
We appreciate your recommendation of the MSP430FR6007 for cost-cutting, and we will evaluate its suitability for our application.
It is good to know that the algorithms remain the same across FR6047, FR6043, and FR6007. Since we are currently testing on the FR6047, this will help simplify the migration process.
Regarding threshold adjustment, we understand that it is generally not required. For water meter applications, can we assume that the MSP430 automatically compensates for aging and sensor sedimentation, eliminating the need for manual threshold adjustment?
For bubble detection, since TI does not provide built-in algorithms, could you suggest possible logic or methods to mitigate the impact of bubbles on measurements?
We appreciate your insights and look forward to your guidance. We will proceed with our evaluation and may reach out if we require further clarification.
Hi,
Regarding threshold adjustment, we understand that it is generally not required. For water meter applications, can we assume that the MSP430 automatically compensates for aging and sensor sedimentation, eliminating the need for manual threshold adjustment?
The MSP430 does NOT compensates for aging and sensor sedimentation. I would say that the lobe algorithm we use for water meter application does not sensitive to the aging issue due to the threshold is actually the ratio of maximum peak. It is dynamic when the maximum peak of the receive signal changes.
I do not have much experience on bubble detection. The only thing I can think of is by checking the amplitude of the receive to indicate if there is valid receive signal.
Best regards,
Cash Hao
Thanks for your response. I have a follow-up question regarding the pulse output interface for a test bench setup using the MSP430FR6047.
In our case, the device is fully assembled and potted with glue, so the circuit is permanently fixed and cannot be modified after assembly. The pulse output pin is always connected to an LED on the circuit itself, and the signal is captured by an optical receiver, which is part of the test bench setup.
However, since the device is battery-powered, we need the pulse output to be active only during calibration and completely disabled afterward to ensure low power consumption. The only way to trigger calibration is through a magnetic cap on the display.
Could you confirm if the MSP430FR6047 supports a pulse output interface in this scenario? If so, could you provide details on:
The hardware pins and software configurations involved (e.g., MTIF_OUT, MTIF_IN, or others).
A recommended circuit design that works with a permanently fixed setup where the circuit cannot be modified after assembly.
Any insights would be greatly appreciated. Thanks!
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