[Dan] salvaged some parts from an old printer a while back and finally found some time to play with them. One of the things he was most interested in is the geared stepper motor seen above. He was able to get it running with an Arduino in no time so he decided to take the project a little bit further. What he ended up with is a stepper motor driver which can be controlled over Bluetooth.
The motor can’t be driven directly, but with a simple motor driver like the L293 chip [Dan] used it’s not hard to interface them with your control hardware of choice. From there he added an ATtiny85 which will take care of the stepping protocol necessary to move the motor. The Bluetooth module he’s using functions as a serial device, making it really simple to interface with the uC. [Dan] uses a pin header to connect the module, so switching to a different type of serial device in the future will be quick and painless.
After the break you can see him sending step commands to the driver board.
mmm capacitors,,, the bigger the better!
thats what i always say!
(unless the inrush would damage a diode ect)
in fact, you could also add a capacitor on the … and on the …
THATS what i actually do, saves a HUGE deal of time in the end.
everywhere i see a resistence (an inch of wire maybe) i add capacitor.
i let the board size/layout determine the biggest that will fit (within rerason)
and try to add both types for ESR reduction
eg: what this guy did, 100uF electro and 0.1 ceramic in parallel ect
its WAY faster to remove capacitors 1 by 1 and see whats nesessary
once the design is finished, (edit working)
rather then wonder if a bug is software or hardware :)
in other words if you KNOW the capacitors are WAY WAY oversized
and it’s not working, then you know the code ect is at fault
PS: love the deadbugged resistor on the LED
i have done somthing similar … the bluetooth module (looking JUST like that but no header and no sheath) had 8 PWM IOs so i just that plus a quad totem poll IC and used it to unlock a claset
I love those little bluetooth modules! There really is no easier way to get your gizmo talking bluetooth… Besides they’re like 7 buck from Deal Extreme! You can’t beat the price with a stick!