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Member Since: March 15, 2010

Country: United Kingdom


Spoken Languages

English (not american :D).

Programming Languages

PIC asm ish Fairly fluent in C


University of Leeds



  • Not quite as simple as I thought. Battery backup works fine by just attaching a battery, however the PMU doesn’t by default charge the battery when there is power - basically it drained my coin cell without recharging it.

    Managed to figure out how to enable charging though:

    sudo apt-get install i2c-tools

    Then do:

    sudo i2cset -f -y 0 0x34 0x35 0xA2

    (You can change the last number to 0xA3 if you want 400uA charge current rather than 100uA).

    This appears to only need doing once - I disconnected the power for a short while and plugged it back in and the register value was still set to the correct value to enable charging.

  • Just got mine and all it takes is to solder on a 3V lithium rechargeable coin cell between Pin30 of the PMU and GND. No other configuration is needed, the internal RTC of the A20 keeps ticking over - I tried unplugging it for 10 minutes and it kept time. I’ll know for sure tomorrow when I plug it back in and see if it still remembers the date/time.

  • Usually the tab is connected to the centre pin on a TO220 package.

  • Sparkfun Electroncs, selling NSA spy technology to the masses (bird not included).

  • Is this available to international customers? (I’m in the UK).

  • In the latest version of my library (https://github.com/TCWORLD/gLCD-Library) I have fixed a bug in the printing fuction which means that the ‘\n’ character now moves to the next line on the screen (it was supposed to in the older versions as well, but I made a mistake that meant it never happened).

  • Speaking of which, it might be time to change the Arduino Stackable Header Kit ( https://www.sparkfun.com/products/10007) to include the 10 pin instead of the 6 pin connector.

  • I suppose. I was thinking it replaces the 6pin header in your shopping cart when you’re buying them B)

  • “so now you need a 10-pin header instead of an 8-pin ”

    Technically you need a 10-pin header instead of one of the 6-pin headers. For an Uno it is now 1x10 + 1x6 + 2x8, whereas it used to be 2x6 + 2x8. Just saying :D

  • The screen is controlled with a Serial link, which tends to be fairly slow - This means that objects may take a couple of 10ths of a second to be drawn. I am working on a new optimised version of the library which speeds things up slightly, but there is a limit to how fast the uC can run.

No public wish lists :(