Hello all.
for a side project, i want to be able to open a file, read ascii characters as numbers (A=41) one by one and substract or add a arbitrary number and write the outcome to another file.
The adding, substracting and leaving alone is already programmed by me, but how do i open and close a file, read a char, change its contents and write it to another file?
does one need a library for this?
do you mean opening a file in the arduino? if so, the file metaphor doesnt really hold up as well. you can write to EEPROM if you like. info on reading/writing EEPROM here: http://www.arduino.cc/en/Reference/EEPROM
keep in mind the EEPROM is only 512 bytes of storage. not very much.
if you mean on the host side of things (ie on a real computer talking to the arduino) then there are millions of ways to write to a file. let us know the language and we can point you in the right direction.
No, no. i want to open a file in processing and control the throughput via the arduino. no problems there. opening a file is a very basic thing. even so basic that it is very difficult to find info about. google did'nt came up with a nice solution anyway...
something like a open dialog would be nice
i think i found the solution:
http://processing.org/learning/topics/savefile1.html
and
http://processing.org/learning/topics/loadfile1.html
globally cover what i was looking for