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How to display ADC data in 12 graphs in real-time


Dear all,

I am working on a project using STM32F750 (custom board), a 7 inch TFT touch LCD (using LTDC), and FreeRTOS v1.

I have 12 analog signals (ECG signals) captured by ADC every 1ms.

I want to plot them (real-time) on 12 different graphs on LCD.

My display refresh rate is usually about 60 Hz. However, when I add 12 dynamic Graph widgets to a screen and add data points in each tick, the refresh rate falls below 15 Hz!

I also tried to disable the ADC and just pass a constant data. But the problem still persists.


Here is what I tried yet:

1-Making a cacheable container and updating the cache -> No effect.

2-Changing the dynamic graph codes so it won't invalidate graph after each point and instead, defining a rectangle and invalidate a moving strip on screen using invalidateRect() -> Refresh rate increased a little bit. However screen flickers

3-Using setFrameRateCompensation(true) -> when I measure screen refresh rate it apparently become 60 Hz again, but when I see it in oscilloscope there are long delays between each several tick.

4-I tried using a custom graph widget instead of dynamic Graph -> problem persists.


I would be really glad if someone can help me to fix this issue.

Associate III

hi, I'm also getting involved in displaying ecg.,here I'm using dynamic graph for displaying 12-lead did you solve this problem..are you completed this project?.as i 'm new to this field ,please help me with this project takes further.,
1. i've basic question, are you used m108 ecg module( data transfers through UART ).? to bring all 12 lead or 12 separate waveform in to single screen display?