well basically, i work on a farm - keeping track of cattle by book often leaves me fed up keeping logs of vaccination times etc...especially when it gets muddy...
anyone know how i can design a simple keypad that records a short series of numbers from 0-9 with a timestamp and stores it to memory making it easily accessable to get the info via usb...
and by the way, there are automated systems that do that but i manage a green eco farm so we dont have intensive farming practices/machines - any help would be much appreciated
Sounds like a simple enough project. Just get yourself:
AVR mirocontroller with SPI and I2C bus and a decent amount of GPIO pins
A Real Time Clock module like this one
Link to keep track of date and time.
SD Card to store your logs
A simple keypad like this
Link
Maybe a Virtual COM USB to serial chip like one of these from FTDI
Link
You will have to implement a SD card driver and FAT filesystem in order to save logs to the SD card. I'm sure code can be found online. You could use the USB connection to set the clock from your computer and the RTC will keep time. The rest of the code simply needs to read the input from the keypad and save it with the time and date to a log file accordingly.
EDIT: You could keep everything but the keypad inside a durable enclosure, and maybe construct it to have a water tight keypad so you could dunk it in water. When you need the data, just open it up and extract the memory card.
... or you could just use a PDA or something, but that's no fun at all.