The stepper/Motor/Driver Pins on the "STM32F407VG-Discover Board & How connect Driver to the Discovery board

[Will Justin]

Hi all,

I have been trying to connect a microstep driver (Haydon DCM8027/55 Driver) to the my discover board, but I don't know how to hookup. I have the following board "STM32F407G-Disc1". I am not sure where the stepper motor/driver pins are located on the Discovery board. Any help would be greatly appreciated.

Thanks,

Will

[T J]

do you have 5V available ?

Maybe you should try 3.3V first, it should still work and you wont run the risk of destroying the selected Disco pins.

Take 5 or 3.3V to pins

PUL+

DIR+

and ENA+

set the other ends onto the Disco board.

[Will Justin]

Hi TJ,

Thanks for your reply, I thought I needed to connect PUL+/-/DIR+/ENA+ to the STM32-Discovery board. Am I right? You are saying take 5V/3.3V from the STM32 board and connect them to PUL+/DIR+/ENA+ of the driver, right?

Thanks,

Will

[T J]

Historically, (1975) DTL was the new technology

Diode / Transistor Logic Best suited to Pull Down Hard...

and we are still using it...

the Pin of your processor can Pull hard Up or Pull Down these days ( 25mA usually)

but your other issue is the requirement of 5V on the LED drive.

You wont be getting 5V from your processor pin, so you cannot drive the LED at 5V

but you can pull low.

some pins are 5V tollerant and you should try to use them, since you can possibly destroy your part over time by over volting..

Luckily for you the LED inside your Motor drive will drop 1 - 2V so the 5V will not be 5V on you pin, but approx 3- 3.7V ( depending on the LED)

but this may be enough leakage to turn on the Motor, so not Ideal.

place a diode in series, to drop a further 0.6V and you will never blow the processor.pin.

Pin- -diode- Pull Down LED pin. 5V on other LED pin.

but of course:

The best method of Voltage translation is through a separate transistor.