#STLTH GEEK BAR Vape Display Replay (Arduino Nano)

Arduino Nano library to control a custom segmented display via I2C replay, using a serial command interface and a mapped logical layout (digits, indicators, icons, bars, RGB ring).

This project abstracts a captured I2C display protocol into high-level commands such as line, digit, rgbfill, and monofill, making the display easy to drive, script, and extend.

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Features

• Software (bit-banged) I2C on A4/A5
• Replay of captured I2C frames (preamble + payload)
• Payload size: 145 bytes
• Robust Serial command parser (no String, low SRAM usage)
• Logical grouping of display areas
• Support for:
  • 7-segment digits
  • 2-segment indicator digits
  • RGB outer ring
  • Bars, icons, UI blocks
• off command that reliably turns everything off
• Debug access via raw payload index control

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Hardware

• MCU: Arduino Nano (ATmega328P)
• I2C (software):
  • SDA → A4
  • SCL → A5

IMPORTANT! disconnect the battery before to make the connections with the arduino, this is because if both are connected sometimes display dont inicialize, If more power is needed then connect the battery AFTER uploading the code and when you can see the display working.

• I2C device address: 0x3C
• External pull-ups on SDA/SCL recommended

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Display Layout Model

Each display line (top / bottom):

[ 2-segment indicator ] [ 7-segment digit ] [ 7-segment digit ]

Example:

• 188 = indicator ON + full 8 + full 8
• 075 = indicator OFF + 7 + 5

The indicator is not a numeric digit.

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Serial Commands

Turn everything off

off

Show current frame

show

Raw payload access (debug)

raw <index> <value>

7-segment digit

digit <slot> <number> [brightness] [dp]

Slots:

• t0 → top, middle digit
• t1 → top, right digit
• b0 → bottom, middle digit
• b1 → bottom, right digit

Full line render

line <top|bottom> <abc> [brightness] [dpMask]

RGB outer ring

rgbfill outer <r> <g> <b>

MONO groups

monofill <group> <value>
mono <group> <index> <value>

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License

MIT / Apache-2.0 / GPL-3.0