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Is it possible to use programmable pic in making our project coin automated changer? Answered

Our project coin automated changer. the user will insert 5 peso coin and it will dispense 5 (1 peso coins) by the use of programmable pic, is it possible? any suggestions? thanks.


The usual coin acceptor just trips a microswitch -- or at most a photodetector -- when the right coin is detected. All you need to do is take that one pulse input and cause five coins to be dispensed. Depending on your mechanical design, that may only require one cycle of the mechanism (in which case no electronics may be needed at all needed) or five appropriately timed cycles (in which case any simple processor will be more then sufficient; the only tricky part is interfacing its output to the dispenser).

This isn't exactly an application which requires a lot of computing power.

(I'm basing this answer on a cash register coin dispenser I dissected, some years ago -- it had a bunch of solenoids which pulled the actuating levers into engagement with the drive shaft, and a single motor which spun that shaft around once to cause the levers to push coins into the chute. No electronics at all; just cams and microswitches and levers and springs.)

Start ANY electronic design by working out what it has to do, what digital I/O it needs, what analogue I/O it needs, does it need serial comms ? USB comms ? THEN you have an idea what to use for a processor. These days, I'd use an 8052 (because its a processor I know well) or an Arduino ( nice programming tools, and wide hardware support) or a Cortex-M3, if I need performance. Steve


7 years ago

It depends on the interface the coin acceptor you use, or if you want to make one from scratch. It is defiantly feasible either way, but it might require a lot of work. If you're not a fluent programmer or do know know very much about electronics, I think this project might be a little too hard for you.

yea. we will make one from scratch. our problem is about the pic we will use and the motor for dispensing..

Dispensing coins, with your own mech and electronics is do-able. Making a reliable coin detector - ie, one that doesn't give money away, because its been cheated by a metal washer, or a foreign coin, or a lead disk is VERY hard. Ultimately, its your money, if you are happy to give it away, because the detection is faulty.....

we will use the usual electronic coin acceptor.. but our problem is the pic.. we dont know what family of pic is going to use. do u have any idea? thanks for your input anyway..