qmk_userspace/OLED_FIX_README.md

OLED Display Fix for 128x32 Screens

Problem

Your OLED code was designed for larger displays (128x64) with 8 rows. Your 128x32 display only has 4 rows × 21 characters, so the 3-row tall graphics take up most of the screen, leaving no room for useful information.

Solution Overview

1. Simplify graphics: Use 1-row tall icons (single character height) instead of 3-row tall graphics
2. Optimize layout: Better use of the 4 available rows
3. Update font file: Replace oversized graphics with compact, readable icons

New Layout for 128x32 (4 rows)

Row 1: [Logo] LAYER NAME
Row 2: [Icon] W-C-S  (modifiers)
Row 3: WPM:045
Row 4: CAPS  SCRL

Files Modified

1. OLED Code (keymap.c)

Replace your current OLED functions with the compact version in:

• oled_redesign_128x32.c (reference implementation)

Key changes:

• Logo: 2 characters instead of 15 (3×5 grid)
• Layer indicators: 2 characters instead of 15 (3×5 grid)
• Modifiers: 4 single characters (W-A-C-S) instead of multi-char graphics
• Text-based layer names: More readable than icons
• Efficient spacing: Uses all 4 rows effectively

2. Font File (glcdfont.c)

Update these character positions with simple icons:

// 0x80-0x81: Logo (2 chars)
0x3E, 0x41, 0x55, 0x55, 0x41, 0x3E,   // 0x80: Keyboard icon
0x3E, 0x41, 0x55, 0x55, 0x41, 0x3E,   // 0x81: Keyboard icon

// 0x92-0x93: Default layer (2 chars)
0x08, 0x1C, 0x3E, 0x7F, 0x2A, 0x2A,   // 0x92: Home icon
0x10, 0x38, 0x7C, 0xFE, 0x54, 0x54,   // 0x93: Home icon

// 0x94-0x95: Symbol layer (2 chars)
0x24, 0x7F, 0x24, 0x7F, 0x24, 0x00,   // 0x94: # symbol
0x24, 0x2A, 0x7F, 0x2A, 0x12, 0x00,   // 0x95: $ symbol

// 0x96-0x97: Navigation layer (2 chars)
0x08, 0x1C, 0x2A, 0x08, 0x08, 0x08,   // 0x96: Up arrow
0x08, 0x08, 0x08, 0x2A, 0x1C, 0x08,   // 0x97: Down arrow

// 0x98-0x9B: Modifier keys (1 char each)
0x66, 0x66, 0x00, 0x7E, 0x66, 0x66,   // 0x98: GUI/Windows
0x7E, 0x09, 0x09, 0x09, 0x7E, 0x00,   // 0x99: ALT
0x3E, 0x41, 0x41, 0x41, 0x22, 0x00,   // 0x9A: CTRL
0x08, 0x1C, 0x2A, 0x08, 0x08, 0x08,   // 0x9B: SHIFT (arrow)

Implementation Steps

Step 1: Update keymap.c OLED functions

Copy the redesigned functions from oled_redesign_128x32.c to your keymap.c, replacing these functions:

• render_logo() → render_logo_compact()
• render_logo2() → (merged into main function)
• render_layer_state() → render_layer_name() + render_layer_icon()
• render_mod_status_gui_alt() → render_modifiers_compact()
• render_mod_status_ctrl_shift() → (merged into modifiers_compact)
• render_status_main() → render_status_compact()
• render_status_secondary() → (use same compact function)
• oled_task_user() → Updated version

Step 2: Update glcdfont.c

1. Find line ~136 where character 0x80 starts
2. Replace the hex values for characters 0x80, 0x81, 0x92-0x9B
3. Keep all other characters (0x00-0x7F for ASCII text)

Step 3: Compile and Test

cd qmk_userspace
bash build_all.sh

Step 4: Flash to Keyboard

Flash the .uf2 files to both halves of your split keyboard.

Customization

Design Your Own Icons

1. Visit: https://helixfonteditor.netlify.com/
2. Each character is 6 pixels wide × 8 pixels tall
3. Export as hex array (6 bytes per character)
4. Copy hex values to glcdfont.c

Character Format

Each character = 6 bytes (one per column):

Byte format (binary): 0bDCBA9876
where 0 = top pixel, 7 = bottom pixel

Example (arrow up):
   ▄     ▄▄▄  ▄ █ ▄   ▄      ▄      ▄   
   █     ███  █ █ █   █      █      █   
= [0x08, 0x1C, 0x2A, 0x08, 0x08, 0x08]

Alternative: Use Text Instead of Icons

If you prefer text-only (no custom graphics):

// In render_modifiers_compact():
if(modifiers & MOD_MASK_GUI)   oled_write_P(PSTR("W"), false);
if(modifiers & MOD_MASK_ALT)   oled_write_P(PSTR("A"), false);
if(modifiers & MOD_MASK_CTRL)  oled_write_P(PSTR("C"), false);
if(modifiers & MOD_MASK_SHIFT) oled_write_P(PSTR("S"), false);

Benefits of This Design

✅ Readable: Text layer names are clearer than multi-row icons ✅ Efficient: Uses all 4 rows with no wasted space ✅ Informative: Shows layer, modifiers, WPM, and caps/scroll lock ✅ Compact: Small icons fit in single row (1 char tall) ✅ Consistent: Same layout on both keyboard halves ✅ Maintainable: Simpler code, easier to modify

Tools Provided

1. oled_font_helper.py: Visualize current font graphics
2. generate_simple_icons.py: Generate simple icon hex values
3. oled_redesign_128x32.c: Complete redesigned OLED code

Next Steps

Would you like me to:

1. Apply these changes directly to your keymap.c and glcdfont.c?
2. Create a different layout design?
3. Design custom icons for specific purposes?
4. Keep some of your original graphics but optimize them?

Let me know how you'd like to proceed!