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Code Changes

The original WeighMyBru² firmware needs a few small changes to work with the hardware used in this build.

Required Changes

1. Display Controller — config.h (line 20)

Change from:

#define DISPLAY_CONTROLLER DISPLAY_CONTROLLER_SSD1306

To:

#define DISPLAY_CONTROLLER DISPLAY_CONTROLLER_SH1106

2. Display Height — config.h (line 24)

Change from:

#define DISPLAY_HEIGHT DISPLAY_HEIGHT_32

To:

#define DISPLAY_HEIGHT DISPLAY_HEIGHT_64

3. Display Rotation — SH1106Driver.h (line 23)

Change from:

oled.setRotation(2);

To:

oled.setRotation(0);

Display upside down?

If the display appears upside down after flashing, change the value back from 0 to 2.

Optional Changes

Always-On Battery Percentage — DisplayLayout.h

By default the battery percentage is not permanently shown on the display. To add it, find line 152 in DisplayLayout.h:

// display.print("WI");

Add the following block immediately after it:

// BATTERY PERCENTAGE
        display.setFont(&FreeMonoBold9pt7b);
        display.setTextSize(1);
        String batteryStr = String(st.batteryPercent) + "%";

        // Calculate text width for right alignment
        int16_t x1, y1;
        uint16_t w, h;
        display.getTextBounds(batteryStr, 0, 0, &x1, &y1, &w, &h);

        // Right-align: set cursor so the text ends at DISPLAY_WIDTH (128)
        int cursorX = DISPLAY_WIDTH - w - 2;
        display.setCursor(cursorX, 57);

        // Blink if battery < 10%
        if (st.batteryPercent < 10) {
            if ((millis() / 500) % 2 == 0) { // Show only every other 500ms
                display.print(batteryStr);
            }
        } else {
            display.print(batteryStr);
        }

This renders the battery percentage right-aligned at the bottom of the display, and blinks it when the battery drops below 10%.