Glue questions

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Niek6502
Posts: 35
Joined: 18 Jul 2025
Location: Alberta, Canada

Re: Glue questions

Post by Niek6502 »

barnacle wrote:
Does the PIC have an option to change the drive speed (rise/fall times) of the output like STM parts do?
Not that I could find.

-Niek.
John West
Posts: 383
Joined: 03 Sep 2002

Re: Glue questions

Post by John West »

barnacle wrote:
Does the PIC have an option to change the drive speed (rise/fall times) of the output like STM parts do?
Quickly looking at the datasheet, I think the SLRCON* "Slew Rate Control" registers might do that. They default to 1, which means slow. And reading further (in the I/O and CLKOUT Timing Specifications), that'll get about 20ns back.
Niek6502
Posts: 35
Joined: 18 Jul 2025
Location: Alberta, Canada

Re: Glue questions

Post by Niek6502 »

John West wrote:
Quickly looking at the datasheet, I think the SLRCON* "Slew Rate Control" registers might do that. They default to 1, which means slow. And reading further (in the I/O and CLKOUT Timing Specifications), that'll get about 20ns back.
Ah - I missed that. I will give that a go over the weekend. Thanks!

-Niek.
Niek6502
Posts: 35
Joined: 18 Jul 2025
Location: Alberta, Canada

Re: Glue questions

Post by Niek6502 »

Niek6502 wrote:
John West wrote:
Quickly looking at the datasheet, I think the SLRCON* "Slew Rate Control" registers might do that. They default to 1, which means slow. And reading further (in the I/O and CLKOUT Timing Specifications), that'll get about 20ns back.
Ah - I missed that. I will give that a go over the weekend.
Did another test:
RigolDS1.png
First input of the scope (yellow line) shows an output of a CLC with maximum slew rate, the second input (blue line) shows a CLC output with the default slow slew rate. Quite a difference. For my rig at 1MHz this will be more than adequate. Thanks John!

-Niek.
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