Cool Pi does not have a TTL interface. If you want to drive a TTL interface screen, you need to use a bridge chip. At present, the MIPI to TTL interface chip supports ICN6211 by default. The following details how to use ICN6211 to drive a TTL interface LCD module.
&mipi_dcphy0 {
status = "okay";
};
&dsi0 {
status = "okay";
dsi0_panel: panel@0 {
status = "okay";
compatible = "simple-panel-dsi";
reg = <0>;
backlight = <&backlight>;
reset-delay-ms = <60>;
enable-delay-ms = <60>;
prepare-delay-ms = <60>;
unprepare-delay-ms = <60>;
disable-delay-ms = <60>;
dsi,flags = <(MIPI_DSI_MODE_VIDEO | MIPI_DSI_MODE_VIDEO_BURST |
MIPI_DSI_MODE_LPM | MIPI_DSI_MODE_EOT_PACKET)>;
dsi,format = <MIPI_DSI_FMT_RGB888>;
dsi,lanes = <2>;
panel-init-sequence = [
23 00 02 7A C1
23 00 02 20 20
23 00 02 21 E0
23 00 02 22 13
23 00 02 23 08
23 00 02 24 04
23 00 02 25 08
23 00 02 26 00
23 00 02 27 08
23 00 02 28 04
23 00 02 29 08
23 00 02 34 80
23 00 02 86 29
23 00 02 B5 A0
23 00 02 5C FF
23 00 02 2A 01
23 00 02 56 92
23 00 02 6B 71
23 00 02 69 15
23 00 02 10 40
23 00 02 11 88
23 00 02 B6 20
23 00 02 51 20
23 00 02 09 10
05 78 01 11
05 1E 01 29
];
panel-exit-sequence = [
05 00 01 28
05 00 01 10
];
disp_timings0: display-timings {
native-mode = <&dsi0_timing0>;
dsi0_timing0: timing0 {
clock-frequency = <25000000>;
hactive = <800>;
vactive = <480>;
hfront-porch = <8>;
hsync-len = <4>;
hback-porch = <8>;
vfront-porch = <8>;
vsync-len = <4>;
vback-porch = <8>;
hsync-active = <0>;
vsync-active = <0>;
de-active = <0>;
pixelclk-active = <0>;
};
};
ports {
#address-cells = <1>;
#size-cells = <0>;
port@0 {
reg = <0>;
panel_in_dsi: endpoint {
remote-endpoint = <&dsi_out_panel>;
};
};
};
};
ports {
#address-cells = <1>;
#size-cells = <0>;
port@1 {
reg = <1>;
dsi_out_panel: endpoint {
remote-endpoint = <&panel_in_dsi>;
};
};
};
};
&dsi0_in_vp3 {
status = "okay";
};
&backlight {
pwms = <&pwm13 0 25000 0>;
status = "okay";
};
&pwm13 {
status = "okay";
pinctrl-names = "active";
pinctrl-0 = <&pwm13m2_pins>;
};
disp_timings0: display-timings {
native-mode = <&dsi0_timing0>;
dsi0_timing0: timing0 {
clock-frequency = <25000000>;
hactive = <800>;
vactive = <480>;
hfront-porch = <8>;
hsync-len = <4>;
hback-porch = <8>;
vfront-porch = <8>;
vsync-len = <4>;
vback-porch = <8>;
hsync-active = <0>;
vsync-active = <0>;
de-active = <0>;
pixelclk-active = <0>;
};
};
- Generate the initialization sequence of ICN6211 according to the LCD specification.
ICN6211 initialization tool ICN6211 Config.rar
Copy the initialization sequence to DTS according to the command format of rockchip.
Command format description：
23 00 02 7A C1
[Command word] [Delay] [Packet length] [Register] [Value]
Note that the last 11 29 command is reserved. This is the DSI standard command to open the display.
panel-init-sequence = [
23 00 02 7A C1
23 00 02 20 20
23 00 02 21 E0
23 00 02 22 13
23 00 02 23 08
23 00 02 24 04
23 00 02 25 08
23 00 02 26 00
23 00 02 27 08
23 00 02 28 04
23 00 02 29 08
23 00 02 34 80
23 00 02 86 29
23 00 02 B5 A0
23 00 02 5C FF
23 00 02 2A 01
23 00 02 56 92
23 00 02 6B 71
23 00 02 69 15
23 00 02 10 40
23 00 02 11 88
23 00 02 B6 20
23 00 02 51 20
23 00 02 09 10
05 78 01 11
05 1E 01 29
];
- The TTL signal can be output normally by recompiling and replacing the kernel.
