User Tools

Site Tools


epaper_display

Differences

This shows you the differences between two versions of the page.

Link to this comparison view

Both sides previous revision Previous revision
Next revision
Previous revision
epaper_display [2011/02/21 03:42]
steve_m [Display controller]
epaper_display [2011/07/27 23:48] (current)
steve_m [Video] embed video
Line 3: Line 3:
 The Motorola F3/MOTOFONE was the first (and still is the only?) mobile phone with an e-paper display. Although this is not a pixel-based display, like found in eBook-readers (e.g. the Amazon Kindle or the B&N nook), it is still quite nice for experimenting with low power microcontroller projects. The Motorola F3/MOTOFONE was the first (and still is the only?) mobile phone with an e-paper display. Although this is not a pixel-based display, like found in eBook-readers (e.g. the Amazon Kindle or the B&N nook), it is still quite nice for experimenting with low power microcontroller projects.
  
-E-paper/​bistable displays have the ability to sustain ​the display content even without the supply of power, so initial idea I had was to build something like a clock, only powering the display when updating it every minute.+E-paper/​bistable displays have the ability to retain ​the display content even without the supply of power, so the initial idea I had was to build something like a clock, only powering the display when updating it every minute.
  
 ===== The display===== ===== The display=====
Line 16: Line 16:
 \\ By the way, since I mentioned the TI Locosto baseband: Maybe someone wants to reverse-engineer the [[http://​bb.osmocom.org/​trac/​wiki/​CalypsoRomloader#​secure-RomloaderonCalypsoplus|serial rom-bootloader]] of this ARM7-based processor, so we can drive the display directly from the phone :-P \\ By the way, since I mentioned the TI Locosto baseband: Maybe someone wants to reverse-engineer the [[http://​bb.osmocom.org/​trac/​wiki/​CalypsoRomloader#​secure-RomloaderonCalypsoplus|serial rom-bootloader]] of this ARM7-based processor, so we can drive the display directly from the phone :-P
 ===== Interfacing with the display ===== ===== Interfacing with the display =====
-Normally, the baseband board and the display/​keypad pcb are connected with a 32-pin connector (exact model unknown). Luckily there are pull-up resistors and capacitors for every needed signal, so I decided to solder some wires there, instead of directly to the connector. The schematics of this phone are floating around the web (just search for **f3_schem.rar**).+Normally, the baseband board and the display/​keypad pcb are connected with a 32-pin connector (exact model unknown). Luckily there are pull-up resistors and capacitors for every needed signal, so I decided to solder some wires there, instead of directly to the connector. The schematics of this phone are floating around the webjust search for **f3_schem.rar**.
  
 |{{:​f3_wires_soldered.jpg?​350|thin wires soldered to the display pcb}}|{{:​f3_display_connector.jpg?​436|the connector of the display}}| |{{:​f3_wires_soldered.jpg?​350|thin wires soldered to the display pcb}}|{{:​f3_display_connector.jpg?​436|the connector of the display}}|
Line 54: Line 54:
 |P1.5|SPI clock|16|SPI_CLK| |P1.5|SPI clock|16|SPI_CLK|
 |P1.6|SPI MOSI|17|SPI_MOSI| |P1.6|SPI MOSI|17|SPI_MOSI|
 +
 +Note: even though the MISO signal is connected in the original phone, there'​s no activity at all, so I left it unconnected. Also, DISPLAY_BUSY0 and 1 seem to be identical.
  
 {{:​msp430_epaper.jpg?​300|Launchpad with connected display}} {{:​msp430_epaper.jpg?​300|Launchpad with connected display}}
Line 59: Line 61:
 ===== Video ===== ===== Video =====
 I've [[http://​www.youtube.com/​watch?​v=HZdV2iKakqA|uploaded a video]], demonstrating the display and Launchpad being used as a low-power clock. I've [[http://​www.youtube.com/​watch?​v=HZdV2iKakqA|uploaded a video]], demonstrating the display and Launchpad being used as a low-power clock.
 +
 +{{youtube>​HZdV2iKakqA}}
  
 A few notes on the video: A few notes on the video:
-  * The timer was actually ​sped up by the factor of 10 for demonstration purposes, so 1 minute on the clock is actually 6 seconds in the video.+  * The timer has been sped up by the factor of 10 for demonstration purposes, so 1 minute on the clock is actually 6 seconds in the video.
   * Completely powering down the display also has its disadvantages. As you can see, the display needs to be initialized every time you power it up again (thus the flickering),​ which isn't needed when just disabling the 32KHz clock.   * Completely powering down the display also has its disadvantages. As you can see, the display needs to be initialized every time you power it up again (thus the flickering),​ which isn't needed when just disabling the 32KHz clock.
 +  * The second row (showing 000000) is just a counter, counting the total hours, and is intended for a runtime test with a goldcap or CR2032 battery.
 ===== Sourcecode ===== ===== Sourcecode =====
 The sourcecode can be found on github: The sourcecode can be found on github:
epaper_display.1298256126.txt.gz ยท Last modified: 2011/02/21 03:42 (external edit)