Difference between revisions of "RPi Screens"

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m (VGA/RGB analog)
(interfacing to Raw LCD panels)
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Replacement screen is about ~$35, another ~$25 for Multitouch Synaptics T1021A touchscreen (I2C + interrupt IO, no docs/drivers).
 
Replacement screen is about ~$35, another ~$25 for Multitouch Synaptics T1021A touchscreen (I2C + interrupt IO, no docs/drivers).
  
The schematics for apples iPhone [http://www.mikrocontroller.net/attachment/127135/iPhone_3Gs_schematics.pdf 3gs] and [http://jumbofiles.com/57ycs8zez45j/iPhone_4G_schematic.pdf.html 4g] suggest they speak DSI, thus they can probably be connected directly. The older iPhones use a "Mobile Pixel Link" connection from National Semiconductor. The 3GS panel (480×320) goes as low as [http://www.aliexpress.com/product-fm/377987722-Replacement-LCD-Glass-Screen-Display-for-iPhone-3GS-wholesalers.html US $14.88], while the 4G one (960×640) can be had for [http://www.aliexpress.com/product-fm/453840894-Replacement-LCD-Glass-Screen-Display-for-iPhone-4G-wholesalers.html US $17.99].
+
The schematics for apples iPhone [http://www.mikrocontroller.net/attachment/127135/iPhone_3Gs_schematics.pdf 3gs] and [http://jumbofiles.com/57ycs8zez45j/iPhone_4G_schematic.pdf.html 4g] suggest they speak DSI, thus they can probably be connected directly. The older iPhones use a "Mobile Pixel Link" connection from National Semiconductor. The 3GS panel (480×320) goes as low as [http://www.aliexpress.com/product-fm/377987722-Replacement-LCD-Glass-Screen-Display-for-iPhone-3GS-wholesalers.html US $14.88], while the 4G one (960×640) can be had for [http://www.aliexpress.com/product-fm/453840894-Replacement-LCD-Glass-Screen-Display-for-iPhone-4G-wholesalers.html US $17.99] or [www.ebay.com/itm/Repair-LCD-Glass-Screen-Display-Iphone-4G-4th-4-GEN-/110680804119 US $14.28]. The connectors used might be an issue, but [http://www.airaccent.com/lcd-screen-fpc-connector-replacement-for-iphone-4g-p-39877.html this connector] might fit.
  
 
Other panels with MIPI DSI: [http://www.panelook.com/modelsearch.php?pagesize=50&order=panel_id&panel_type=&product_composition=&brand_family=&panel_size_inch=&resolution_pixels=&brightness=-1&gray_depth=&viewing_angle_function=&lamp_type=&signal_type_category=MIPI&rohs_compliance=&button=Search www.panelook.com]
 
Other panels with MIPI DSI: [http://www.panelook.com/modelsearch.php?pagesize=50&order=panel_id&panel_type=&product_composition=&brand_family=&panel_size_inch=&resolution_pixels=&brightness=-1&gray_depth=&viewing_angle_function=&lamp_type=&signal_type_category=MIPI&rohs_compliance=&button=Search www.panelook.com]

Revision as of 12:58, 8 February 2012


Back to the Hub.


Hardware & Peripherals:

Hardware and Hardware History.

Low-level Peripherals and Expansion Boards.

Screens, Cases and Other Peripherals.


Supported Standards

The following display outputs are supported on the board:

  • Composite video (NTSC and PAL) via an RCA plug (the yellow socket on your TV) or SCART socket.
  • HDMI 1.3a standard output.
  • Display Serial Interface (DSI) - via unpopulated 15-way flat flex connector.

These interfaces allow the use of a broad range of displays, including:

  • Televisions (HDMI or composite).
  • Computer monitors (HDMI/DVI-D cable) (VGA monitors would require either a composite or HDMI to VGA or component scan converter box).
  • DLP/Laser Pico Projectors (HDMI/DVI-D cable).
  • RAW LCD panels (DSI + interfacing hardware)
  • Composite and HDMI outputs can not be used at the same time (one or the other.)

HDMI

Directly from the board.

DVI

With an inexpensive passive HDMI to DVI-D cable or convertor.

Composite video

Composite video (NTSC and PAL) via an RCA plug, directly from the board.

VGA/RGB analog

The Broadcom BCM2835 only provides HDMI output and composite output. RGB and other signals needed by RGB, S-VIDEO or VGA connectors are however not provided.

A couple of options for VGA or component RGB outputs, bridging from either HDMI or the MIPI DSI interface:

Firstly, the following *might* work. Beagleboard people have reported various levels of success (mainly "issues"):

http://www.hdfury.com/

Something similar:

http://www.fit-pc.com/web/fit-pc2/accessories/fit-vga/

...it may need to be modified as described here:

http://blog.galemin.com/2011/03/dvi-d-to-vga-converter-for-beagleboard-xm/

Alternatively, it may be possible to design an expansion board that plugs into the LCD headers on the R.Pi. Here is something similar for Beagleboard:

http://boardzoo.com/product_info12.php

Some more converters that should work:

Potential RGB interfacing chips:

They emit Hsync, Vsync and RGB w/ about 8 bits each (sometimes, it's called "MIPI DPI")

This one outputs analog RGB, but is hard to find (obsolete?):

The SOC (system on a chip) does not support any kind of analog component video, including VGA, since the SOC is designed for mobile phone use where this would not be a requirement. Additional componenty would be needed to generate RGB signals. Additional componentry would push the price beyond the $25 target and therefore won't happen.

interfacing to Raw LCD panels

Nokia N900 has 800x480 DCS LCD (afaik its like DSI, but has build in framebuffer). Replacement screen is about ~$40 (~$50 with 4pin resistive touchscreen).

Nokia N8 has AMOLED 360x640 pixels DSI LCD. Replacement screen is about ~$35, another ~$25 for Multitouch Synaptics T1021A touchscreen (I2C + interrupt IO, no docs/drivers).

The schematics for apples iPhone 3gs and 4g suggest they speak DSI, thus they can probably be connected directly. The older iPhones use a "Mobile Pixel Link" connection from National Semiconductor. The 3GS panel (480×320) goes as low as US $14.88, while the 4G one (960×640) can be had for US $17.99 or [www.ebay.com/itm/Repair-LCD-Glass-Screen-Display-Iphone-4G-4th-4-GEN-/110680804119 US $14.28]. The connectors used might be an issue, but this connector might fit.

Other panels with MIPI DSI: www.panelook.com

Potential LVDS interfacing chips:

TC358764/5 Display Bridge (MIPI® DSI to LVDS)

DVI receiver TFP401A, TFP403, or TFP501 + LVDS transmitter SN75LVDS83B or SN65LVDS93A (Mentioned earlier fit-VGA is build around TFP401A, probably many more "active" DVI2VGA cables are build the same way)


I2C/SPI ADC can be used to interface 4 pin resistive Touch Screens, For example STMPE812A. Texas Instruments has a solution for 4 or 8 wire touchscreens using their rather cheap MSP4309.


16x2 LCD Displays

The old-style 2-line, 16-character LCD displays can be commonly controlled over UART, thus providing a cheap way to display values for sensors etc.

References