Req: PWM pin reassignment

Marcos' unmaintained, but still in-use, Puma for FreeEMS circuit board/hardware design!
Post Reply
User avatar
KW1252
LQFP112 - Up with the play
Posts: 166
Joined: Tue Jan 15, 2008 5:31 pm

Req: PWM pin reassignment

Post by KW1252 »

I had a chat with Fred about PWM, and an interesting discovery was made concerning PWM pin assignments.

Right now, there are two drivers connected to ports PP0.1 and two signal outputs at PP6.7, while ports 2 through 5 are for stepper controller.

The request is to rearrange PWM output to pins 0 through 3, and so that drivers connects to P0 and P2. This allows flexibility in PWM configuration, allowing either two 16-bit drivers or two 8-bit drivers with two 8-bit signal outputs.
User avatar
Fred
Moderator
Posts: 15431
Joined: Tue Jan 15, 2008 2:31 pm
Location: Home sweet home!
Contact:

Re: Req: PWM pin reassignment

Post by Fred »

+1

Marcos, put the two on-board drivers on two 16 bit channels and put the two matched pins out as GP. That way you can have two 16 bit pwm drivers and two GP pins OR 4 8 bit pwm outputs, two with drivers, two without.

The way it is at the moment sets it up with the same 4 8 bit outputs, but in 16 bit mode you get one on board and one off board, and one GP on board driver and one GP output header.

The reason I prefer the other option is that the majority of people are going to want the best performance out of the on board drivers, ie, idle control for one output and boost for the other.

Fred
DIYEFI.org - where Open Source means Open Source, and Free means Freedom
FreeEMS.org - the open source engine management system
FreeEMS dev diary and its comments thread and my turbo truck!
n00bs, do NOT PM or email tech questions! Use the forum!
The ever growing list of FreeEMS success stories!
User avatar
nitrousnrg
LQFP144 - On Top Of The Game
Posts: 468
Joined: Tue Jun 24, 2008 5:31 pm

Re: Req: PWM pin reassignment

Post by nitrousnrg »

Ack, good one.

Is in the TODO now.
Marcos
Post Reply