hi,
as you will know, the Arduino Mega provides for
DPins 44-46 pwm,
and DPins 50-53 are for hardware SPI
Now I'm actually curious about what these pins are for on the Arduino Due ?
Just sort of regular DPins (no pwm, no interrupts, no SPI, no special different functionality) ?
Or is there something important one should know about them for the Due?
See attached by Gray Nomad
You do understand, I hope, that the Mega is an AVR 8-bit architure and the Due is a 32-bit ARM core?
Atmega designs microcontrollers for a wide marketplace which does not include Arduino. So, Arduino core team somewhat tries to map pin usage, but this effort is not perfect by any means!
thank you,
of course I know about this AVR and ARM thing, and I've also already seen this pinout scheme, but I don't understand all those abbreviated designations like
C.18 C.9 PWMH3 PWML2 D44 PWMH5 CANTX1 RXD2,
so please again:
what about 44-46 and about 50-53 on the Due ?
hasn't got really no one information about those Due pins ??
Everything you ever wanted to know about the pins of a Due is exceptionally well documented in Gray Nomads color coded documentation sheet. You just need to study the chart for a bit starting with the key in the upper left corner. Look at the pin of interest and decode the color coded key from the upper left. Let's start with your question of pins 44-46:
Pin 44: given the yellow circle surrounding the pin, it denotes a high current pin that can source 15 ma, sink 9 ma. Next is The magenta block with 101 inside. This denotes it is physically pin 101 on the IC. Next is the Yellow C.19 which says it is port C, bit 19. Next is white PWMH5 which decodes to SAM3X8E function pin that is a PWM output. Finally we have the gray D44 which tells us it is Arduino digital pin 44.
Does that help understanding Due pins? Hopefully you're not color blind and you can decode the rest for yourself... No insult intended since many men are red/green impaired.
Now I'm actually curious about what these pins are for on the Arduino Due ?
A while back, I've created a pdf (sorted by pin function): Due Pin Function Table
hi,
yes, indeed I suffer from a Protanopie (as we call in German terminology "red-green-blindness". Also my father and my brother suffer from it.
I'm confused because Arduino says about Due pwm is just
PWM: Pins 2 to 13
but for the Mega they say:
PWM: Pins 2 to 13 and 44-46
so what is correct now about 44-46 for the Due?
what Arduino says or what the scheme says?
Either one must be wrong, of course.
and what is correct now about 50-53 for the Due?
ps,
@dlloyd: just saw your chart, but it's confusing to me, too - I don't understand the symbols.
I'm just a hobbyist, I have absolutely no technical education and my English is also quite poor unfortunately.
I'm confused because Arduino says about Due pwm is just PWM: Pins 2 to 13
This is correct when using analogWrite(pin, value)
Other PWM pins on the Due are available, but you cannot use them without installing a special library or including some advanced register-level code.
I'm always just using analogWrite for pwm (L293) , no additional techniques.
So something like PWMH5 is important to me only in those cases as it provides pwm for analogWrite by Sketch libraries.
So back to my TOP question, as I still don't see through all of these obscured features:
what is the difference of Arduino Due Pins 44-46 and 50-53 vs. Arduino Mega (just for Sketch) ?
what is the difference of Arduino Due Pins 44-46 and 50-53 vs. Arduino Mega (just for Sketch) ?
[b]Pin Board Function Other Function(s)[/b]
44 Mega I/O PWM
44 Due I/O
45 Mega I/O PWM
45 Due I/O
46 Mega I/O PWM
46 Due I/O
50 Mega I/O SPI (MISO)
50 Due I/O
51 Mega I/O SPI (MOSI)
51 Due I/O
52 Mega I/O SPI (SCK)
52 Due I/O SPI (SS)
53 Mega I/O SPI (SS)
53 Due I/O CANTX1
On the Due, there are other pin functions are available.
that's really impressive, thank you!
the pwm thing is what I meanwhile expected (pwm on Mega, nothing but Dpin on Due).
actually very surprising is the SPI thing:
50 Mega I/O SPI (MISO)
50 Due I/O
51 Mega I/O SPI (MOSI)
51 Due I/O
52 Mega I/O SPI (SCK)
52 Due I/O SPI (SS)
53 Mega I/O SPI (SS)
53 Due I/O CANTX1
no MISO and no MOSI on Due, but diverging SCK, SS, and CAN bus (?).
Anyway, that helps a lot, thanks again!