The new video is of our hardware controlling the E-Ink Display Module. We chose a 5 frame image; a Sierpinski Triangle. This is calculated and displayed at less than 5 frames in 3 seconds entirely on our ePS prototype board. Control is by a command interpreter running on the ePS Display. These prototypes help us make the final design decisions for the three production boards, one for each size display. Our prototype boards were assembled on the pick and place machine which was featured in our first movie. We make hardware not movies.
Here is a photo of a Large ePS Display mounted as a shield on an Arduino Mega, control is via Rx, Tx Serial or SPI:
This project is to assemble, test, ship and support of a series of epaper displays. The product contains an E-Ink display, display driver components and microController in one easy to use package. They are available in three display sizes. Bitmap graphics and text are placed on the display in the size, font and position desired. Control is with SPI, Serial or I2C ports. The ePs works standalone or controlled by a uController and operates on 3 to 16 VDC. The medium and large ePS circuit board is suitable for securing in a project box or even plugging into the top of an Arduino shield stack.
We wanted to display numbers, words and graphics in a more attractive way than the segmented LCD displays in our inventory permit. We started looking for a higher quality display to use indoors and out, a display flexible in use and frugal on power. We need to display measured and set point temperatures in ambient light. Instead of blocky numbers we thought we wanted our display to look like this:
We found a remarkable line of epaper displays and products that use the same display technology used in the ebook Kindle. The display technology is called E-Ink. Pervasive Displays (PDI) is the manufacturer. PDI recently announced the release of three small E-Ink displays to the parts market via stocking distribution. We bought some and have been impressed.
We have loaded these E-Ink displays with images we have created for testing and demos. We have placed them beside our other displays and studied them for weeks indoors and outdoors comparing them with other display technologies. Initially put off a bit by the light gray "paper" and dark gray "ink" we have come to appreciate that they are superior for many target applications. We find E-Ink displays to be more pleasant to see and read than our other displays under a large range of lighting conditions.
This E-Ink technology produces a reflective image like a book or newspaper rather than an image created with a light source. The significance of this must be experienced to be fully appreciated. It is easy and comfortable to read an image that does not glow, does not flicker. The image is easy to read in low light and easy to illuminate. The image is easier to read in direct sunlight than any other display we have tested. Most other displays wash out completely under bright lighting conditions. The angle of view is phenomenal, almost 180 degrees in all directions. We can place our choice of font, size and graphics anywhere within the active display area that we want.
The more we compare these displays with others the more appealing they become. Now our temperature controller display looks like this:
The image stays on the display when disconnected from power just like you see above. We can turn power off to the display and put the uController into deep sleep to conserve power, the sleeping uC consumes a few uAmps. When the display is changed it is powered up drawing milli-Amps and again turned off to save power. The display may be left on for frequent updates. The display is driven through the a 40 wire flexible flat cable, substantial driver circuitry and careful program timing which PDI calls complex waveform generation. We like these E-Ink displays so much that we have designed the ePaperShield a product that consists of an E-Ink display, the necessary driver circuitry, a uController and accessories. This makes a package that is easy to use and is general in application. We are looking forward to developing projects based on ePaperShields.
E-Ink displays are made of small capsules containing tiny black and white particles moved about by electrical charge on a matrix. The black is the "ink" and the white is the "paper". This forms an image on the epaper surface, like this:
E-Ink displays are remarkable. Individual pixels may be bit mapped, are easy to read in bright sunlight, are more visible in dim light than reflective LCD displays. E-Ink displays maintain the image when completely disconnected from power.
These E-Ink displays were designed for a revolutionary application as labels for retail store shelves. This development kit for use as tags on retail store shelves features the same three E-Ink displays PDI has made available to us. A transmitter is used to change the information individually on each shelf label. This application is promoted with display development systems like this:
Note the small, medium and large displays. These are the displays that have been made available to us. This AdapTag Development Kit is available from PDI and contains all the circuitry to drive these displays wirelessly. We hard wire to our displays.
We designate these E-Ink displays by active display area and overall size. Each display has an additional two pixel wide border that is controlled as a single pixel and beyond that an additional border that is not active image. The images may be rotated to any angle.
These E-Ink Display Modules are:
Small 128 x 96 pixels 111 pixels per inch 1.6 x 1.2 inches
Medium 200 x 96 pixels 111 pixels per inch 2.3 x 1.2 inches
Large 264 x 176 pixels. 117 pixels per inch 2.8 x 1.8 inches
We purchased some displays and development kits. We breadboarded the ePaperShield. We have partnered with a surface mount assembly facility and the developer of the uController breakout board we selected for controlling the E-Ink displays. Our product will be assembled in their pick and place facility. We have scheduled initial assembly.
We are assembling five ePS Display products, each include one E-Ink Display Module. Three sizes of ePS Displays and two sizes of ePS Displays with development enhancements we are calling ePS Developer Displays
ePS Displays* (Small, Medium, Large) include one E-Ink display module, driver circuitry, uController and additional memory
ePS Developer Displays* (Medium and Large) are ePS Displays plus uSD card holder, USB-ISP... The Large includes a breakout header.
*Note: All ePS Displays accept Arduino shield headers.
To learn how many words would fit on the smallest display we chose a limerick and settled on an 11 pixel font. This fills the display nicely. Notice the descender on the y in young has 4 pixels of clearance above the t in Bright. We tried the limerick set in a 9 pixel font. It was quite legible however left a fourth of the display empty. Rather than search for another text we increased the font size to 11 pixels. Our displays now unleash our imaginations.
There are several ways to send instructions via choices of serial communication connections. Bitmaps may be stored in the ePS display memory and used as needed. The ePaperShield Developer uController may be used to program your own graphic display language, or use ours. These programs may be copied to standard ePS Displays. As designed, ASCII instructions are used to tell the ePaperShield what to display, where to display it and how large to display it. They may be programmed to do much much more.
We are assembling the ePaperShield in two forms; the standard ePS Display and an ePS Developer Display. The ePS Display includes E-Ink driver circuitry, a Cortex M3 uController, a graphic memory chip, SPI, Serial, and I2C communications. These standard displays run on 3-16 vdc.
The ePS Developer Display has the same E-Ink driver circuitry, Cortex M3 uController, SPI, Serial and I2C communications plus a uSD memory card holder, a USB port, bootloader and also run on 3-16 vdc.
The ePS Display is ready to go and easy to use right out of the package for those whom would like an eInk display, but do not want to worry about the complex details of sending data or the driver circuitry. An Arduino sketch or other micro-controller can transmit a few simple ASCII commands to update the display. The firmware in the ePS ARM processor can handle the details of updating the eInk display module. Choose; SPI, Serial, or I2C; connect; send a carriage return and the ePS Display will respond. When powered on the display cycles through a demonstration. When configured for use the test and demonstration screens are replaced with your display parameters.
The ePS Developer Display has additional components and features not included in the ePS Display. Create your own graphics display program or use ours. It is possible to program the Cortex M3 ARM uController for a complete embedded solution built into the display. or investigate the intimate details of animating E-Ink. We included features to make this easy for example refresh times can be intimately altered. The GNU arm tools, and some libraries, will get you started.The ePS Developer Display includes additional communication choices such as USB Flash ISP and makes available several General Purpose Input and Output ports as header holes.
Programming the uController in the ePS Developer Display as USB Drive is an innovation in ease of use for creating, testing and installing programs. The ePS Developer Display flash program memory may be accessed as a USB Drive. The USB connection can provide power and communicate with the ePS uController, like an Arduino. Howver, unlike an Arduino, press the Flash Memory Programming button and it presents itself to the computer as a USB Drive. Paste your program into the flash memory and the boot loader starts running your program. If you make a mistake, change your program and press the Flash Memory Programming button again and copy a new .bin file to flash. The flash boot loader is in ROM which prevents the uController from becoming bricked by overwriting the boot loader with an errant program.
The ePS Display and the ePS Developer Display are Arduino friendly with header holes provided in the Medium and Large ePS to match the Arduino shield header layout. This includes power, ground, Serial and SPI pins. There is not enough room on the PCB of the small ePS to support the programmer hardware. The ePS Developer Display runs code similar to the Arduino Due which also features a Cortex M3 uController. We are told it is possible to program this uController using the Arduino IDE and Sketches.
This project is to shrink and assemble the PDI EPDv05 display driver and add a uController to make the ePaperShield like this:
The PDI circuitry and flexible flat cable connector are moved to the back of the board behind the display where we are placing the uController, memory and general purpose input/output connections. With this product, custom displays for electronics projects can be created as needed. Custom fonts and graphics programs may be created and added to your library, to the Open Source font library or to the Public Domain.
Last minute photo; One of the first protype boards showing the back side. This is the Large and Medium ePS pcb layout. The display folds around to the front for mounting:
Reward Selection Guide
There are three E-Ink Display Modules; Small, Medium and Large. These require driver hardware.
There are three ePS Displays which include an E-Ink Display Module they are also Small, Medium and Large. They also include the uController, additional display memory and Serial, SPI and I2C capability. In addition they have several unassigned GPIO pins available.
There are two ePS Developer Displays Medium and Large which include an E-Ink Display Module and USB, uSD, ISP button, Reset button and other development features. Programs developed on these Developer products may be loaded onto an ePS Display. This facilitates the creation of appliances with the uController embedded in the display.
There is an E-Ink Sample Set featuring an ePS Developer Display with one each of the E-Ink Display Module. Since the E-Ink modules retain their image without power they may be tested individually.
There is an ePS Display "Makers" set that includes a Developer Display and one each of the three ePS Displays. This is four separate displays for use creating custom programs for the ePS Displays.
We expect you will find these products useful for many applications and appliances.
Risks and challenges
The biggest challenge may be to attract enough interest to achieve our assembly cost goals. The hardware works. Pick and place assembly tests have been performed on the parts. The flexible flat cable connector is the assembly speed limiting part and it "places perfectly at nearly full speed."
Unexpected events such as part availability leads to even a single part delivery or error can delay the assembly schedule. We are eager to put these ePS displays in your hands and respond to your feedback. The limiting parts may be the E-Ink Display Modules which have been quoted by PDI to be available in 90 days. These are manufactured to order to according to their production schedule. We expect PDI to fill our order from inventory and production as fast as they are able. We will assemble the uController/Driver boards ahead of the display arrival so final testing, packaging and shipping may immediately follow arrival of the E-Ink display modules.
Another challenge is our pricing. Does it cover all the costs we will encounter? We have gone over and over the spreadsheets, believe the pricing is satisfactory. There is really only one way to find out how close our budgets are; that is launch, assemble and examine the results.Learn about accountability on Kickstarter
- (28 days)