23 May 2010

Minor Project - external EEPROM management: - more diagrams
















Above top is the pinout diagram for the 24xx256, & below that is how the 24LC08 is connected to the Arduino. The pinout's the same anyway..
Note that Analog pins 4 & 5 are used for the I2C communication, so they can't be used for any other purpose.
Pull-up resistors R1 & R2 are 10 kilOhms.

It's all fairly simple really (she says, crossing her fingers & toes)..
Hard-wiring a shield is now fairly simple - i just have to Stop Procrastinating!!

The other pins can be used for breadboarded inputs & outputs - for inputs from the 'Great Weekend Datalogging Project' - more about that later..

This program has been revisited.

2 comments:

  1. there's a school of thought that says the pull-up resistors R1 & R2 are not actually necessary because of the internal pull-ups of the 24xx256 chip itself..
    Hmmmm.. well, it's less to do, i s'pose..

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  2. "Hard-wiring a shield is now fairly simple.."
    HAHAHAHAHA - famous last words!!

    In the end, i just gave up. DON'T buy a battery-powered soldering iron (& Stop Laughing - it seemed like a good idea at the time!) unless you enjoy wasting hours on daggy joints that are probably 'dry' anyway, faffing around trying to de-short circuits from adjacent pins, & dealing with bolshie, uncooperative header-pins..
    (sigh)
    There should be an icon for "(sigh)"ing - all you arty, graphics mavens out there could prob'ly run one up while i'm still staring glassy-eyed at Flash's confusing menagerie of icons! I know they'll prob'ly fly me to the Moon & back if i ask them to, but i don't even know how to jog round the block with it..
    Arrrggh!!

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