Bit Angle Modulation (BAM) in a PIC

[Mike, K8LH]

Actually, you could do it with just 2 instructions per update (using 18F and 40-MHz clock) but it would require a blanking interval of sorts at end-of-period or at some other point in time to update/refresh duty cycle values. In this particular case it would actually be easier to implement with BAM or MIBAM compared to the more traditional PWM methods.

As a side note. I think I have a method for using MIBAM modulation on that little 20-LED charlieplexed array. The refresh rate works out to a whopping 520-Hz per LED which would allow you to fade each individual LED from black to full to black (511 steps) in less than a second. The 520-Hz per LED (or per column) rate is achieved by using a 1.5-usec step or an overall refresh rate of 2600-Hz (with a 1920-usec frame rate). Man I'm good (LOL). Seriously though, this model or method suggests that we could achieve a very respectable refresh rate even with a standard mux'd 8x8 matrix.

Mike

[Darrel Taylor]

Charlieplexed MIBAM now you're scaring me Mike.

Still don't have the full-port version working yet.
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[Mike, K8LH]

Charlieplexed MIBAM now you're scaring me Mike.

Still don't have the full-port version working yet.
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What do you mean "full-port version", Sir?

[Darrel Taylor]

What do you mean "full-port version", Sir?

Your previous contribution starting at post#55.
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[Mike, K8LH]

Sorry, I misunderstood.

I coded the full-port-at-a-time method driver in assembly language as part of a 16F886 project and will test it on a prototype board sometime soon.

I also coded the Charlieplexed 20-LED MIBAM driver in an assembly language project for a 16F886 host.

Both projects simply have variables and the ISR driver setup for simulation so they're far from complete demos'. When I get something up-n'-runnin' I'll post a video and the assembly code, if anyone asks for it.

Regards, Mike, K8LH

[Darrel Taylor]

When I get something up-n'-runnin' I'll post a video and the assembly code, if anyone asks for it.

OK, so let me go ahead and take care of that part ...

Hey Mike,

When you get it all working, could you post the code ... and maybe show a video of it in action?
It'll help me figure out how to do it in PicBasic Pro.