Change QEP pins

Sourabh Sharma

Prodigy 125 points

Is there a way to make any three GPIO pins suitable for QEP operation?

over 9 years ago

0 Richard Poley over 9 years ago

TI__Mastermind 27200 points

There is usually a limited choice of pins for QEP inputs. Which device are you using?

0 Sourabh Sharma over 9 years ago in reply to Richard Poley

Prodigy 125 points

28069
One of the standard QEP pin is occupied for some other purposes

0 Richard Poley over 9 years ago in reply to Sourabh Sharma

TI__Mastermind 27200 points

On F28069 there are basically two groups of I/O pins available for each of the two QEP modules: EQEP1 is available on GPIO20-23 or GPIO 50-53. EQEP2 is available on either GPIO24-27 or GPIO 54-57 (EQEP2 index and strobe are also on GPIO 30 & 31 respectively. Unfortunately these are the only options.

The place to look is Tables 1-64 & 1-65 on pages 126 & 127 of the Users guide:

Newer devices have an I/O cross-bar which give a richer choice of I/O pins, but on F2806x we only have those options above.

Regards,

Richard

0 Sourabh Sharma over 9 years ago in reply to Richard Poley

Prodigy 125 points

Can you please recommend such newer devices?
By I/O cross-bar, do you mean I can use pins from different QEP modules? For ex: EQEP_A_1, EQEP_B_1, EQEP_Z_2 as inputs for a QEP module.

0 Richard Poley over 9 years ago in reply to Sourabh Sharma

TI__Mastermind 27200 points

The devices I had in mind are the F2837xD, F2837xS, and F2807x families. In each case there is a wider I/O mux with more options for peripheral pin routing. There is also an input X-bar which allows certain peripheral inputs to be routed freely to any I/O pin. I was thinking that the QEP was among these peripherals, but unfortunately it is not. So, for the QEP, there is a little more flexibility on these parts but no X-bar connectivity. Sorry about that.
Section 4.5 in the F2837xD datasheet shows an example of what I mean.
www.ti.com/.../sprs880g.pdf
Regards,
Richard

C2000™︎ microcontrollers

C2000 microcontrollers forum

Change QEP pins