st7789: work in progress on display refactor

Signed-off-by: deadprogram <ron@hybridgroup.com>

st7789/registers.go

@@ -21,19 +21,19 @@ const (
 	RAMWR     = 0x2C
 	RAMRD     = 0x2E
 	PTLAR     = 0x30
+	VSCRDEF   = 0x33
+	TEOFF     = 0x34
+	TEON      = 0x35
+	VSCRSADD  = 0x37
 	COLMOD    = 0x3A
 	MADCTL    = 0x36
-	MADCTL_MY  = 0x80
+	GSCAN     = 0x45
-	MADCTL_MX  = 0x40
+	PWCTRL1   = 0xD0
-	MADCTL_MV  = 0x20
-	MADCTL_ML  = 0x10
-	MADCTL_RGB = 0x00
-	MADCTL_BGR = 0x08
-	MADCTL_MH  = 0x04
 	RDID1     = 0xDA
 	RDID2     = 0xDB
 	RDID3     = 0xDC
 	RDID4     = 0xDD
+	RAMCTRL   = 0xB0
 	FRMCTR1   = 0xB1
 	RGBCTRL   = 0xB1
 	FRMCTR2   = 0xB2
@@ -41,19 +41,26 @@ const (
 	FRMCTR3   = 0xB3
 	INVCTR    = 0xB4
 	DISSET5   = 0xB6
-	PWCTR1     = 0xC0
+	GCTRL     = 0xB7
+	VCOMS     = 0xBB
+	LCMCTRL   = 0xC0
 	PWCTR2    = 0xC1
-	PWCTR3     = 0xC2
+	VDVVRHEN  = 0xC2
-	PWCTR4     = 0xC3
+	VRHS      = 0xC3
-	PWCTR5     = 0xC4
+	VDVS      = 0xC4
 	VMCTR1    = 0xC5
 	FRCTRL2   = 0xC6
+	PVGAMCTRL = 0xE0
+	NVGAMCTRL = 0xE1
 	PWCTR6    = 0xFC
-	GMCTRP1    = 0xE0
+
-	GMCTRN1    = 0xE1
+	MADCTL_RGB       = 0x00
-	GSCAN      = 0x45
+	MADCTL_ROWORDER  = 0x80
-	VSCRDEF    = 0x33
+	MADCTL_COLORDER  = 0x40
-	VSCRSADD   = 0x37
+	MADCTL_SWAPXY    = 0x20
+	MADCTL_SCANORDER = 0x10
+	MADCTL_BGR       = 0x08
+	MADCTL_MH        = 0x04
 
 	ColorRGB444 ColorFormat = 0b011
 	ColorRGB565 ColorFormat = 0b101

st7789/st7789.go

@@ -76,6 +76,8 @@ type Config struct {
 	ColumnOffset     int16
 	FrameRate        FrameRate
 	VSyncLines       int16
+	IdleModePorch    byte
+	PartialModePorch byte
 
 	// Gamma control. Look in the LCD panel datasheet or provided example code
 	// to find these values. If not set, the defaults will be used.
@@ -134,7 +136,7 @@ func (d *DeviceOf[T]) Configure(cfg Config) {
 	if cfg.VSyncLines >= 2 && cfg.VSyncLines <= 254 {
 		d.vSyncLines = cfg.VSyncLines
 	} else {
-		d.vSyncLines = 16
+		d.vSyncLines = 0 // Default: no VSYNC pause
 	}
 
 	d.batchLength = int32(d.width)
@@ -150,10 +152,12 @@ func (d *DeviceOf[T]) Configure(cfg Config) {
 	d.startWrite()
 	d.sendCommand(SWRESET, nil) // Soft reset
 	d.endWrite()
-	time.Sleep(150 * time.Millisecond) //
-	d.startWrite()
 
-	d.sendCommand(SLPOUT, nil) // Exit sleep mode
+	time.Sleep(150 * time.Millisecond) //
+
+	d.startWrite()
+	// enable frame sync signal if used
+	d.sendCommand(TEON, nil)
 
 	// Memory initialization
 	var zeroColor T
@@ -164,51 +168,108 @@ func (d *DeviceOf[T]) Configure(cfg Config) {
 		// Use default RGB565 color format.
 		d.setColorFormat(ColorRGB565) // 16 bits per pixel
 	}
-	time.Sleep(10 * time.Millisecond)
-
-	d.setRotation(d.rotation) // Memory orientation
-
-	d.setWindow(0, 0, d.width, d.height)   // Full draw window
-	d.fillScreen(color.RGBA{0, 0, 0, 255}) // Clear screen
-
-	// Framerate
-	d.sendCommand(FRCTRL2, []byte{byte(d.frameRate)}) // Frame rate for normal mode (default 60Hz)
 
 	// Frame vertical sync and "porch"
 	//
 	// Front and back porch controls vertical scanline sync time before and after
 	// a frame, where memory can be safely written without tearing.
 	//
-	fp := uint8(d.vSyncLines / 2)         // Split the desired pause half and half
+	// TODO: is this correct? fp := uint8(d.vSyncLines / 2)         // Split the desired pause half and half
-	bp := uint8(d.vSyncLines - int16(fp)) // between front and back porch.
+	fp := byte(0x0c)
+	// TODO: is this correct? bp := uint8(d.vSyncLines - int16(fp)) // between front and back porch.
+	bp := byte(0x0c)
+	if cfg.IdleModePorch == 0 {
+		cfg.IdleModePorch = 0x22 // Default value
+	}
+	if cfg.PartialModePorch == 0 {
+		cfg.PartialModePorch = 0x22 // Default value
+	}
 
 	d.sendCommand(PORCTRL, []byte{
 		bp,                   // Back porch 5bit     (0x7F max 0x08 default)
 		fp,                   // Front porch 5bit    (0x7F max 0x08 default)
-		0x00, // Seprarate porch     (TODO: what is this?)
+		0x00,                 // Separate porch      (TODO: what is this?)
-		0x22, // Idle mode porch     (4bit-back 4bit-front 0x22 default)
+		cfg.IdleModePorch,    // Idle mode porch     (4bit-back 4bit-front 0x22 default)
-		0x22, // Partial mode porch  (4bit-back 4bit-front 0x22 default)
+		cfg.PartialModePorch, // Partial mode porch  (4bit-back 4bit-front 0x22 default)
 	})
 
-	// Ready to display
+	// LCM control, power on sequence
-	d.sendCommand(INVON, nil)         // Inversion ON
+	d.sendCommand(LCMCTRL, []byte{0x2C})
-	time.Sleep(10 * time.Millisecond) //
+
+	// VDV and VRH Command Enable - 0x01 power on sequence
+	d.sendCommand(VDVVRHEN, []byte{0x01})
+
+	// VRH Set - 0x12 5.3+( vcom+vcom offset+vdv)
+	d.sendCommand(VRHS, []byte{0x12})
+
+	// VDV Set - 0x20 0V
+	d.sendCommand(VDVS, []byte{0x20})
+
+	// PWCTRL1 Power control 1 - power on sequence
+	d.sendCommand(PWCTRL1, []byte{0xA4, 0xA1})
+
+	// Framerate
+	d.sendCommand(FRCTRL2, []byte{byte(d.frameRate)}) // Frame rate for normal mode (default 60Hz)
+
+	// As noted in https://github.com/pimoroni/pimoroni-pico/issues/1040
+	// this is required to avoid a weird light grey banding issue with low brightness green.
+	// The banding is not visible without tweaking gamma settings (GMCTRP1 & GMCTRN1) but
+	// it makes sense to fix it anyway.
+	d.sendCommand(RAMCTRL, []byte{0x00, 0xC0})
 
 	// Set gamma tables, if configured.
 	if len(cfg.PVGAMCTRL) == 14 {
-		d.sendCommand(GMCTRP1, cfg.PVGAMCTRL) // PVGAMCTRL: Positive Voltage Gamma Control
+		d.sendCommand(PVGAMCTRL, cfg.PVGAMCTRL) // PVGAMCTRL: Positive Voltage Gamma Control
 	}
 	if len(cfg.NVGAMCTRL) == 14 {
-		d.sendCommand(GMCTRN1, cfg.NVGAMCTRL) // NVGAMCTRL: Negative Voltage Gamma Control
+		d.sendCommand(NVGAMCTRL, cfg.NVGAMCTRL) // NVGAMCTRL: Negative Voltage Gamma Control
 	}
 
-	d.sendCommand(NORON, nil)         // Normal mode ON
+	switch {
-	time.Sleep(10 * time.Millisecond) //
+	case d.width == 240 && d.height == 240:
+		// 	command(reg::GCTRL, 1, "\x14");
+		// Gate Control - power on sequence for 240x240
+		d.sendCommand(GCTRL, []byte{0x35})
 
+		// command(reg::VCOMS, 1, "\x37");
+		// VCOM Setting
+		d.sendCommand(VCOMS, []byte{0x37})
+
+		// command(reg::GMCTRP1, 14, "\xD0\x04\x0D\x11\x13\x2B\x3F\x54\x4C\x18\x0D\x0B\x1F\x23");
+		d.sendCommand(PVGAMCTRL, []byte{0xD0, 0x04, 0x0D, 0x11, 0x13, 0x2B, 0x3F, 0x54, 0x4C, 0x18, 0x0D, 0x0B, 0x1F, 0x23})
+
+		// command(reg::GMCTRN1, 14, "\xD0\x04\x0C\x11\x13\x2C\x3F\x44\x51\x2F\x1F\x1F\x20\x23");
+		d.sendCommand(NVGAMCTRL, []byte{0xD0, 0x04, 0x0C, 0x11, 0x13, 0x2C, 0x3F, 0x44, 0x51, 0x2F, 0x1F, 0x1F, 0x20, 0x23})
+	case d.width == 320 && d.height == 240:
+		// Gate Control - power on sequence for 320x240
+		d.sendCommand(GCTRL, []byte{0x35})
+
+		// VCOM Setting - 0.875V
+		d.sendCommand(VCOMS, []byte{0x1f})
+
+		// command(reg::GMCTRP1, 14, "\xD0\x08\x11\x08\x0C\x15\x39\x33\x50\x36\x13\x14\x29\x2D");
+		d.sendCommand(PVGAMCTRL, []byte{0xD0, 0x08, 0x11, 0x08, 0x0C, 0x15, 0x39, 0x33, 0x50, 0x36, 0x13, 0x14, 0x29, 0x2D})
+
+		// command(reg::GMCTRN1, 14, "\xD0\x08\x10\x08\x06\x06\x39\x44\x51\x0B\x16\x14\x2F\x31");
+		d.sendCommand(NVGAMCTRL, []byte{0xD0, 0x08, 0x10, 0x08, 0x06, 0x06, 0x39, 0x44, 0x51, 0x0B, 0x16, 0x14, 0x2F, 0x31})
+	}
+
+	// Ready to display
+	d.sendCommand(INVON, nil)  // Inversion ON
+	d.sendCommand(SLPOUT, nil) // Exit sleep mode
 	d.sendCommand(DISPON, nil) // Screen ON
-	time.Sleep(10 * time.Millisecond) //
-
 	d.endWrite()
+
+	time.Sleep(100 * time.Millisecond)
+
+	d.startWrite()
+	d.setRotation(d.rotation)              // Memory orientation
+	d.setWindow(0, 0, d.width, d.height)   // Full draw window
+	d.fillScreen(color.RGBA{0, 0, 0, 255}) // Clear screen
+	d.endWrite()
+
+	time.Sleep(50 * time.Millisecond)
+
 	d.blPin.High() // Backlight ON
 }
 
@@ -519,18 +580,20 @@ func (d *DeviceOf[T]) setRotation(rotation Rotation) error {
 	madctl := uint8(0)
 	switch rotation % 4 {
 	case drivers.Rotation0:
+		madctl = MADCTL_COLORDER
+		madctl |= MADCTL_SWAPXY | MADCTL_SCANORDER
 		d.rowOffset = 0
 		d.columnOffset = 0
 	case drivers.Rotation90:
-		madctl = MADCTL_MX | MADCTL_MV
+		madctl = MADCTL_COLORDER | MADCTL_SWAPXY
 		d.rowOffset = 0
 		d.columnOffset = 0
 	case drivers.Rotation180:
-		madctl = MADCTL_MX | MADCTL_MY
+		madctl = MADCTL_COLORDER | MADCTL_ROWORDER
 		d.rowOffset = d.rowOffsetCfg
 		d.columnOffset = d.columnOffsetCfg
 	case drivers.Rotation270:
-		madctl = MADCTL_MY | MADCTL_MV
+		madctl = MADCTL_ROWORDER | MADCTL_SWAPXY
 		d.rowOffset = d.columnOffsetCfg
 		d.columnOffset = d.rowOffsetCfg
 	}