The LB1946 is a very nice chopper driver, the only downside is that it has a serial interface. So, for a project I need to control some steppers. I have a box full of printer boards, picked this one from and old epson inkjet because it had the same chips and also looks like I can chop it in half with a hacksaw and use them as they are.
The logic and the original power supply were toast so I used another I had at hand. To make some tests I hacked the PowerSwitch circuit from Objective Development to send raw commands and spin the motor with an usb interface.
At the end it doesn’t look quite like the original but it works. Still can’t get more than 1000 steps per second but I think that’s because of the supply. Now that I have the basic code working I’ll have to make a parallel interface so I can use them with EMC.
Sourcecode / References:
- V-USB a software-only implementation of a low-speed USB device for Atmel’sAVR® microcontrollers
- lb1946_usb.tar.bz2 – Firmware and host software to control the lb1946.
- LB1946 datasheet (local mirror, may be outdated)
Pics:
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- avr based LB1946 controller with usb interface.