Dear All,
Have rapidly moved on from PWMOUT to HPWM ( in full-bridge mode) to get forward & back as well as speed control. This simplifies the electronics in my H-bridge considerably (only 4 transistors instead of 8). I am using PNP darlingtons as the "top" transistors (A & C) and NPNs as the "bottom" two (B & D). Hence I am using polarity 2.
All ticketty-boo. However, even though this works perfectly it is now tying up 4 pins of my 14M and I really need as many pins as possible for other jobs. So I got to wondering about whether it might be possible to use HPWM in half-bridge mode (i.e. only 2 pins used) and somehow control 4 transistors with the two complimentary outputs using some more electronics.
In the apparent continuing absence of the HPWM motor control datasheet does the team think there would be enough information in the two outputs to give me control of forward and back as well as speed?
I appreciate I could use another PICaxe for the moter control as a slave from a main processor, but this is a school project and as we are going to have to fund a stack of these I'm trying to keep the per-unit cost to a minimum
(and we've already got one slave controlling the steering servo!)
Thanks again,
Mark
Have rapidly moved on from PWMOUT to HPWM ( in full-bridge mode) to get forward & back as well as speed control. This simplifies the electronics in my H-bridge considerably (only 4 transistors instead of 8). I am using PNP darlingtons as the "top" transistors (A & C) and NPNs as the "bottom" two (B & D). Hence I am using polarity 2.
All ticketty-boo. However, even though this works perfectly it is now tying up 4 pins of my 14M and I really need as many pins as possible for other jobs. So I got to wondering about whether it might be possible to use HPWM in half-bridge mode (i.e. only 2 pins used) and somehow control 4 transistors with the two complimentary outputs using some more electronics.
In the apparent continuing absence of the HPWM motor control datasheet does the team think there would be enough information in the two outputs to give me control of forward and back as well as speed?
I appreciate I could use another PICaxe for the moter control as a slave from a main processor, but this is a school project and as we are going to have to fund a stack of these I'm trying to keep the per-unit cost to a minimum
(and we've already got one slave controlling the steering servo!)Thanks again,
Mark
Last edited: