diff options
Diffstat (limited to 'ssd1306.lua')
| -rw-r--r-- | ssd1306.lua | 61 |
1 files changed, 61 insertions, 0 deletions
diff --git a/ssd1306.lua b/ssd1306.lua new file mode 100644 index 0000000..54923bc --- /dev/null +++ b/ssd1306.lua @@ -0,0 +1,61 @@ +local ssd1306 = {} + +local s_CONTRAST = 0x81 +local s_ENTIRE_ON = 0xa4 +local s_NORM_INV = 0xa6 +local s_DISP = 0xae +local s_MEM_ADDR = 0x20 +local s_COL_ADDR = 0x21 +local s_PAGE_ADDR = 0x22 +local s_DISP_START_LINE = 0x40 +local s_SEG_REMAP = 0xa0 +local s_MUX_RATIO = 0xa8 +local s_COM_OUT_DIR = 0xc0 +local s_DISP_OFFSET = 0xd3 +local s_COM_PIN_CFG = 0xda +local s_DISP_CLK_DIV = 0xd5 +local s_PRECHARGE = 0xd9 +local s_VCOM_DESEL = 0xdb +local s_CHARGE_PUMP = 0x8d + +function ssd1306.wc(byte) + return ssd1306.wd({0x80, byte}) +end + +function ssd1306.wd(data) + i2c.start(0) + if not i2c.address(0, 0x3c, i2c.TRANSMITTER) then + return false + end + i2c.write(0, data) + i2c.stop(0) + return true +end + +function ssd1306.init(width, height) + ssd1306.w = width + ssd1306.h = height + local tab = {s_DISP, s_MEM_ADDR, 0x01, s_DISP_START_LINE, s_SEG_REMAP + 0x01, + s_MUX_RATIO, height - 1, s_COM_OUT_DIR + 0x08, s_DISP_OFFSET, 0x00, + s_COM_PIN_CFG, height == 32 and 0x02 or 0x12, s_DISP_CLK_DIV, 0x80, + s_PRECHARGE, 0x88, s_VCOM_DESEL, 0x30, s_CONTRAST, 0x80, s_ENTIRE_ON, + s_NORM_INV, s_CHARGE_PUMP, 0x14, s_DISP + 0x01, s_COL_ADDR, 0, 127, + s_PAGE_ADDR, 0, 7} + for i, v in ipairs(tab) do + ssd1306.wc(v) + end + + ssd1306.fb = string.rep("0", width * height / 8) +end + +function ssd1306.show() + local txbuf = {0x40} + for i = 1, ssd1306.w * ssd1306.h / 8, 128 do + for j = 0, 127 do + txbuf[j+2] = string.byte(ssd1306.fb, i + j) + end + ssd1306.wd(txbuf) + end +end + +return ssd1306 |