sh1106 v0.1.0

Minimal SH1106 128x64 I2C OLED driver.

Application scenarios

• A 1.3-inch status display.
• A menu on a handheld instrument.
• A bring-up display for a new board.

Contract

void sh1106_init(sh1106_port_t port);
void sh1106_clear(sh1106_port_t port);
void sh1106_set_contrast(sh1106_port_t port, uint8_t value);
void sh1106_write_page(sh1106_port_t port, uint8_t page, uint8_t column,
                       const uint8_t *data, uint8_t width);

• write sends commands with control 0x00 and data with control 0x40.
• init sends the SH1106 DC-DC, timing, and COM sequence.
• clear fills all eight pages with zeros.
• write_page writes one page (8 pixels) at column.
• The caller owns the page buffer; no framebuffer or font is included.

Parameters

• I2C address 0x3C or 0x3D is selected in the adapter.
• width must fit column + width <= 128.
• Contrast 0..255; 0xFF is a common start.

Memory and timing

• 8 bytes of state plus the port context.
• clear sends 1024 data bytes; split into adapter-sized chunks.
• SH1106 has 132 columns; visible RAM starts at column 2.

Integration

sh1106_port_t port = board_sh1106_port();
sh1106_init(port);
sh1106_clear(port);
uint8_t row[128] = {0};
row[0] = 0x3C;
sh1106_write_page(port, 2, 0, row, 128);

Adapters

• The adapter handles the I2C address, bus speed, and reset pin.
• Reference: u8g2 u8x8_d_ssd1306_128x64_noname.c SH1106 sequence (BSD-2-Clause).
• Verify the panel's DC-DC and COM configuration.

When not to use

• An SSD1306 panel; use the ssd1306 unit.
• Text and graphics; add a font/renderer above this page API.

Verification

make test covers the init sequence, clear, contrast, and a page write with

the SH1106 column offset.

void *context;
uint8_t (*write)(void *context, uint8_t control, const uint8_t *data, uint16_t length);