3.3 logic level of uC32 and Arduino shields compatibility

[painterguy1995]

Hi,

I'm planning to buy uC32 and it uses 3.3V logic level. As far as I know all Arduino Uno shields (or any Arduino shield) are 5V, so can I connect those shields to uC32? Could you please guide me? Thanks.

[JColvin]

Hi @painterguy1995,

I apologize for the delay.

It depends on what connections are using the 5V. Most of the digital pins on the uC32 can technically handle 5V signals, though they cannot provide 5V output. The ADC header on the uC32 cannot handle 5V signals though.

Let me know if you have any questions about this.

Thanks,
JColvin

[painterguy1995]

1 hour ago, JColvin said:

I apologize for the delay.

It depends on what connections are using the 5V. Most of the digital pins on the uC32 can technically handle 5V signals, though they cannot provide 5V output. The ADC header on the uC32 cannot handle 5V signals though.

Thank you!

Let me clarify. So, most of the digital pins on the uC32 can technically read 5V signals but cannot output 5V.

You said that the ADC header on the uC32 cannot handle 5V signals though. I think it means that since ADC does analog to digital conversion therefore uC32 cannot handle 5V input on its pins to convert it into digital representation. Please correct me if I'm wrong. Thanks.

[JColvin]

Hi @painterguy1995,

That is correct; the ADC that is present on the PIC32MX chip is not equipped to handle voltages above 3.3V.

The digital I/O have both clamp diodes and current limiting resistors which allows them to handle 5V inputs.

Let me know if you have any questions about this.

Thanks,
JColvin

[painterguy1995]

Hi @JColvin

Thanks a lot for the help!

Question 1:

How much power uC32 board could supply to the attached devices? What's the maximum current which could be supplied by each pin separately and combined at the same time? I'd really appreciate it if you could help me with it.

In the attached picture I have highlighted the pins I'm talking about. 

I believe 3V pin stands for 3.3V. 

Question 2:

Does uC32 come preloaded with Arduino bootloader?

 

[JColvin]

Hi @painterguy1995,

As per the reference manual, https://reference.digilentinc.com/reference/microprocessor/uc32/reference-manual#power_supply, the 3.3V regulator is limited to 500 mA and the 5V regulator is limited to 1A. Each individual digital I/O pin is limited to 18 mA.

I'm not certain which 3V pin you are referring to. The one the arrow points to is labeled as "3V3", which is 3.3V.

I'm not certain what you mean by "Arduino" bootloader, but it does come loaded with a bootloader so that it can be configured through the Arduino IDE, yes.

Let me know if you have any other questions.

Thanks,
JColvin

[painterguy1995]

Hi:

The following is from reference manual of uC32.

Quote

 

The uC32 board is designed to be used with the Multi-Platform IDE (MPIDE). MPIDE is a modified version of the

Arduino IDE that supports the PIC32 microprocessors and is backwards-compatible with the Arduino IDE. The

MPIDE uses a serial communications port to communicate with a boot loader running on the uC32 board. The

serial port on the uC32 board is implemented using an FTDI FT232R USB serial converter. Before attempting to use

the MPIDE to communicate with the uC32, the appropriate USB device driver must be installed.

[...]

Using the Microchip development tools to program the uC32 board will cause the boot loader to be erased. To use

the board with the MPIDE again, it is necessary to program the boot loader back onto the board. The boot loader

image can be downloaded from the Digilent Uno32 product page.

 

 

Do I need to install the driver? I plan to use uC32 with Arduino IDE. I'd appreciate it if you could clarify this. Thank you!

 

 

[JColvin]

Hi @painterguy1995,

I believe (it's been awhile) that the needed drivers either come with the Arduino IDE or are part of the Digilent Core for the Arduino IDE (installation instructions available on our Wiki here: https://reference.digilentinc.com/learn/software/tutorials/digilent-core-install/start). *Edit: I checked and the necessary drivers are included with the Digilent Core.

The instructions say to use Arduino 1.6.9, but I have used the same core up through 1.8.12 without any issues or needing to install drivers; Windows . My understanding is that MPIDE has been depreciated and is no longer used.

Let me know if you have any questions.

Thanks,
JColvin

[painterguy1995]

Thanks a lot, @JColvin It's vert nice of you.