Modulating signal help

[Ghostbear]

Hi all,

I'm after a bit of help.

I'm working on a circuit that generates a pwm signal that feeds into a transistorised AND gate to an emmitter.
I also need it doing a couple of other tings at the same time when a button is pressed (increment a counter, trigger two pins high/low and generate a 2nd PWM signal that also feeds through the AND gate to the emitter.

I've got the whole shebang working using a 14m2, two transistors plus switch. what I'm wondering is, is there a way to build the AND gate function of the two transistors into the Picaxe?

I can get it working as an AND gate, but can't get it doing anything else at the moment.

In all honesty, given the difference to the overall circuit is two transistors it's not crucial if It's not possible, but this is more for a refinement to the circuit....

Thanks all

 

[AllyCat]

Hi,

It's not directly supported by PICaxe Basic, nor its documentation, but the 14M2 base chip (and several others) has a "Data Signal Modulator" on Legs 5 - 8. See section 23 of the base Microchip data sheet in the "Advanced Technical Details" linked here.

Start by looking at the pinning Table 1 on page 6 of the data sheet, but then you will need to look at section 23 and understand how PICaxe accesses the Special Function Registers (PEEK/POKESFR).

Cheers, Alan.