6 independent PWM outputs

3 posts / 0 new

Mon, 04/15/2019 - 05:18

max19

Hi,

I'm using the labjack T7 Pro for outputing multiple PWM signals to different actuators. Currently I'm using 4 outputs (DIO0, DIO2, DIO3, DIO4). I'm planning a new system, for which I would require 6 PWM outputs. However, only pins DIO0, DIO2, DIO3, DIO4, DIO5 are capable of outputing PWM singals. Is there a way to configure pin DIO1 to be used as a PWM output pin too? Any help/ideas is appreciated!

Mon, 04/15/2019 - 09:45

LabJack Support

The T4 processor only has

The T4 processor only has hardware support for 5 PWM outputs, so that is a hard limit. I see 2 options:

1. If your frequency is slow enough you could use a Lua script to produce PWM output on lots of DO. You can do timed loops in Lua with an interval as small as 1 ms, so that is the best case limit of your duty cycle resolution.

2. Add a 2nd device. A T4 for example would get you 2 more PWM outputs. Another advantage to using multiple devices is you can get different PWM frequencies on each device, as that is quite limited on 1 device.

Mon, 04/15/2019 - 10:36

max19

Thanks for the reply.

Unfortunately, 1ms resolution is not feasible for my application.

The second approach seems promising though. I'll have a look at that.

Thanks again!