OLED Module

Drive an SSD1306-based monochrome OLED display (the cheap 0.96" 128×64 panels everyone has) over I2C. Send text, draw rectangles, blit 1-bit bitmaps; the firmware buffers everything off-screen until you call show().

Firmware setup

; platformio.ini
build_flags = -DCONDUYT_MODULE_OLED
lib_deps =
    adafruit/Adafruit GFX Library
    adafruit/Adafruit SSD1306

#include <Conduyt.h>

ConduytSerial transport(Serial, 115200);
ConduytDevice device("DisplayBot", "1.0.0", transport);

void setup() {
  Serial.begin(115200);
  Wire.begin();
  device.addModule(new ConduytModuleOLED());
  device.begin();
}

void loop() {
  device.poll();
}

Wiring

SSD1306 OLED      Board
─────────         ─────
SDA           ──► SDA pin (Uno: A4, ESP32: 21, Pico: GP4)
SCL           ──► SCL pin (Uno: A5, ESP32: 22, Pico: GP5)
VCC           ──► 3V3
GND           ──► GND

I2C address: most modules are 0x3C. A few clones with the SA0 pad jumpered to VDD are 0x3D. Pass addr=0 to the wrapper to use the firmware default of 0x3C.

Host usage

JavaScript

import { ConduytDevice } from 'conduyt-js'
import { SerialTransport } from 'conduyt-js/transports/serial'
import { ConduytOLED } from 'conduyt-js/modules/oled'

const device = await ConduytDevice.connect(new SerialTransport({ path: '<YOUR_PORT>' }))
const oled = new ConduytOLED(device)

await oled.begin(128, 64)
await oled.clear()
await oled.text(0, 0,  1, 'Hello')
await oled.text(0, 16, 2, 'CONDUYT')
await oled.drawRect(0, 48, 128, 16, true)   // filled bar
await oled.show()

Python

from conduyt import ConduytDevice
from conduyt.transports.serial import SerialTransport
from conduyt.modules import ConduytOLED

device = ConduytDevice(SerialTransport('<YOUR_PORT>'))
await device.connect()

oled = ConduytOLED(device, module_id=0)
await oled.begin(width=128, height=64, i2c_addr=0x3C)
await oled.clear()
await oled.text(0, 0, 1, "Hello")
await oled.show()

Command reference

Command	ID	Payload	Description
Begin	`0x01`	`width(1) + height(1) + addr(1)`	Init the panel. addr=0 → 0x3C default
Clear	`0x02`	(none)	Zero the off-screen buffer
Text	`0x03`	`x(1) + y(1) + size(1) + str(N)`	Draw text. Remaining bytes are the string
DrawRect	`0x04`	`x(1) + y(1) + w(1) + h(1) + fill(1)`	Outline (fill=0) or filled rect
DrawBitmap	`0x05`	`x(1) + y(1) + w(1) + h(1) + data(N)`	1-bit bitmap, ceil(w*h/8) bytes
Show	`0x06`	(none)	Flush off-screen buffer to the panel

Notes

All draw commands paint into an off-screen buffer. Nothing appears on the panel until you call show().
Text bytes are limited to 64 chars per packet by the firmware buffer — chunk longer strings yourself.
size is the Adafruit_GFX text scale. 1 = 6×8 pixels per character, 2 = 12×16, etc.
Bitmaps are 1 bit per pixel, MSB-first within each byte. A 16×16 bitmap is 32 bytes.