My network:
  Ribbonfarm section
  Youtube channel
  Livejournal (rus)
  Spaceway forum
 Random thoughts
 Random stories
 Sound camera (RF)
 Timelapse camera
 MicroBook reader
 Multiband camera
 Multiband camera (RF)
 Tesla coils
 Soviet calculator
 3D printer
 Quadrotor UAV
 Box of sunshine
 Molten salt battery
 LCD curtains
 Aprom OS
 METEOR M decoder
 M.A.X. Remake
 Rocket Land
 Random games
Artwork & photo:
 Time lapses
 Concepts - Rhego
 Concepts - Pella
 Random Art
 Lunar eclipse
Orbiter addons:
 Collision SDK
 Orbiter Shipyard
 Shukra Station
 OSH gallery
 Shukra gallery
 Orulex gallery
 OGLAClient gallery
 Ship Generator
 Shipgen manual
 Orbiter flight gallery
   05.10.2014 - Microbook, hardware

 Most parts are clearly visible on the prototype

Full schematics and firmware
The core is the Atmega328p microcontroller.
Microsd card slot is connected to it directly, over SPI.
Nokia 5110 screen is also linked by SPI.
The screens in a nice wrapper can be obtained from China, on ebay, i.e. here.
On the bottom there are 4 buttons and 2 debug LEDs.

The 32Kb FRAM chip, FM24W256 is connected over I2C.
Firmware access pattern assumes FRAM, or other type of NVRAM.
You could use a regular flash/eeprom chip or even AVR's internal eeprom, but FRAM have a nearly unlimited write cycles, and write speed is the same as read speed, which opens up some possibilities.
The memory holds a list of books opened, with current positions, it stores the position on every page flip, menu locations/settings on every change and button press, and so on.
This allows you to completely turn off the device at any time, then power it on and have it in the same state it was at power off. Convenient and power-saving.

The power supply consist of 3 ICs.
MAX660, doubles the 2-3V from the solar panel to 4-6V needed for the charger.
MAX1555, a LiPo charge controller, with the battery attached to it.
There is a power switch between the battery and the rest of the circuit, so it keeps charging when turned off.
After the battery there is a MCP1252 charge pump voltage stabiliser, giving out 3.3V.
A line goes from the battery to the Atmega's ADC, across a voltage divider, to monitor battery charge level.

All this fits on a rather simple two sided 50x60mm PCB.

 PCB traces

 The same, for real

 The only hardware issue found to date is the lack of a case

 3D printing helps, but just barely

Wery nice! Are You going to share sources?

Best regards
26.05.2018 19:30 - Evg

Hi, are you available to work on some similar projects ?
27.03.2018 05:02 - Wober Dane

I actually thought about making something with this or 10.2" displays of theirs.
However i'm out of budget for the moment, and these things are expensive even without intercontinental delivery.

Not sure how much sense would it make - even 2.7" one alone cost as much as two Mk1 microbooks, and 7.4" one would be 4 times more expensive than that.
In other words, it would escalate from "easy DIY project" to "ridiculous".
Even Mk2 is already almost past the "makes sense" line, and is only there because 2.7" displays are common enough in various kits to be reasonable.
26.02.2015 02:36 - Artlav - how about this one?
25.02.2015 13:59 - Max

Absolutely gorgeous. But, the commentary about larger display still applies: is there a chance to see mk3 (or macrobook) e-ink reader which is about 20 cm wide - so it fits in a4 paper easily. And, ideally, with some touch capabilities so there's no need to bother with soldering buttons on the side?
25.02.2015 13:53 - Max

Comments disabled for lack of purpose and excess of spam.
If you have a comment on some project, ping me on the corresponding forum.


  ADSE 0.9.3   © 2005-2018,