Sunday, December 6, 2009

Wise Clock 2 - Good news and bad news

Updated Feb 18/2010

Note: This posting is no longer relevant, from both the hardware and the software perspectives.
I'll keep it around just for the record.

The good news is that there is a new release, probably this year's last, of the Wise Clock 2 software.
Beside the expected bug fixes (related to alarm, thanks Mike B), there are also a couple of new features, both based on libraries published in the Arduino forum:
  • support for the infrared receiver, for commands from Sony TV remote controls;
  • alarm and other user settings are now saved into RTC's non-volatile memory (thanks Jeff S, matt).
The bad news is that you will need to do a bit more soldering for the above-mentioned software to work. Here is what happened: the infrared receiver and the Plus button are connected to the same D2 pin.

If you are not going to use the infrared receiver at all (bad idea, since you loose functionality), no hardware modifications are required. If you decide that the infrared receiver must do its job, then you need to replace a trace and a resistor. The idea is to move the Plus button onto pin D3, leaving the infrared receiver on D2 (also associated with INT2).

Edit (Jan/10): Turns out that the IR receiver is mandatory after all, due to the software. If it is not soldered (or inserted in a 3-pin socket), it must be "replaced" with a 10k resistor that pulls up D2 input (that is, D2 is connected to Vcc through a 10k resistor).

These are the steps:
  • on the top (parts) face of the board, cut the trace to the Plus button and the resistor R13, as shown below in yellow;
  • on the back of the board, solder a wire between the newly disconnected pin of button Plus and pin 4 of the microcontroller;
  • solder a new 10k resistor between pin 4 of the microcontroller and Vcc; an easy way to do this is shown in the image below;

These hardware "bug fixes" will allow the infrared receiver and the Plus button to coexist peacefully. The latest software release has the Plus button on D3.

Note: The latest batch of Duino644 boards, shipped after Dec 7, 2009, have, by design, the IR receiver on D2 and the Plus button on D3, so they won't require any hacking.

The "Wise Clock 2 User Manual" should get an update as well.

Talking about storage, notice that Duino644 has four places where data can be stored persistently (that is, it is not lost after a power shutdown):
  1. SD card;
  2. on-board external EEPROM;
  3. RTC non-volatile RAM, powered by the backup battery;
  4. internal (micro controller) EEPROM.

One last news is related to the LED display panel from Sure Electronics: they now sell green 24x16 displays.