Skip to main content

Arduino Due and the SD Card Reader

 

Arduino Due and the SD Card Reader

Filed in Microcontrollers on Jan.16, 2019

The next board to test with the SD Card Readers is the Arduino Due.

 
Arduino Due

This is a little different sort of beast, more powerful. But there are some differences with other Arduinos that can get us in trouble.

Differences between Due and the Mega:

Microcontroller AT91SAM3X8E (Due) ATmega1280 (mega2560)
Operating Voltage 3.3V 5V
Input Voltage (recommended) 7-12V 7-12V
Input Voltage (limits) 6-16V 6-20V
Digital I/O Pins 54 (12 provide PWM output) 54 (15 provide PWM)
Analog Input Pins 12 16
Analog Output Pins 2 (DAC) 0
DC input per Pin 3 – 15mA (see chart) 40 mA
Total DC Output Current 130 mA 200 mA
DC Current for 3.3V Pin 800 mA 50 mA (up to 150 mA, if no FTDI)
DC Current for 5V Pin 800 mA 200 mA
Flash Memory 512 KB all available for the user applications 128 KB (4 KB used by bootloader)
SRAM 96 KB (two banks: 64KB and 32KB) 8 KB
Clock Speed 84MHZ 16MHZ

 

  • The Due CPU operates at 3.3V, while most Arduinos CPUs operate at 5.0v
    • Connecting higher voltages to I/O, like the 5V commonly used with the other Arduino boards will damage the Due.
  • The Due is not as heavy duty as most other Arduinos
  • The Due has 1 dedicated SPI port, and 4 multipurpose USART/SPI ports.
  • The SPI port is only routed to the 6 pin header.
    • This header is not used for In Circuit Programming on the Due.
  • The Due does not have any EEPROM
  • The Due uses a ARM chip instead of an AVR
    • might cause problems with some libraries that only support AVR.
  • Many older shield are not compatible with the Due
  • The Due has the ability to act as a USB host for peripherals connected to the SerialUSB port.
  • The Due is capable of higher resolution on analog reads and writes
    • It can support up to 12-bit ADC and PWM resolutions.
  • The Due has expanded functionality on its SPI bus.
 
Due Pinout

Considering these differences, I connected the Due up to our SD Card test circuit as follows:

SD Card Testing Setup

SD Card Pin Arduino Due Pin
VCC POWER 3.3V
GND POWER GND7-12V
MISO SPI-1
MOSI SPI-4
SCK SPI-3
CS DI-10
Other Connections
Kill Switch DI-2


 
SPI Connector

Once everything was hooked up appropriately, I plugged the Due into the USB port on my laptop.  After a few seconds, another new com port showed up for the Due.

 

 
Arduino Due Setup in IDE

I set the IDE up to compile for the Auduino Due on the programming port (nearest the power connector). Then I selected the matching Com Port.

After setting up the Due, I loaded the CardInfo program.  Again, the only change for any of the Card Reader programs was to specify the correct Chip Select Pin that matched the hardware wiring (pin 10 in this case).

The program compiled with no problems.  The compiler output looks a little different…

 
CardInfo Compile 1 of 2

 
CardInfo Compile 2 of 2

It shows the progress of uploading the program, then the progress on verifying the upload.

The program works fine, as did all of the other Card Reader programs that I tested (as in prior posts on this subject).

 
CardInfo Success

Finally, I changed the SD Card out to a 32GB card, and ran CardInfo on it.  No problems there…

 
CardInfo on 32GB Card

So, it was not as difficult as I thought it might be.

Comments

Post a Comment

Popular posts from this blog

Building the W8NX Short Trap Dipole

Image
  Building the W8NX Short Trap Dipole Filed in Antennas on May.31, 2021 For the past five years, I have been operating the lower bands (30, 40 and 80 meters) with a trap dipole that was modeled after a web article written by John DeGood NU3E. [1] While the antenna performed well, a monsoon storm last summer beat it up enough that the antenna wire broke at the center balun. So I climbed the tower and lowered the remains of the antenna to the ground for repairs. On closer examination, I discovered that the relentless Arizona sun had taken its toll on the traps. The insulation on the exposed ends of the coax had rotted away. They were still working, but would need to be rebuilt and weatherized to insure good operation many years into the future. Since I was going to have to rebuild the antenna, I started thinking about whether this antenna met my current needs and wishes. I had been wanting to get on 160 meters at this QTH for some time, but my small back yard would
Read more

Yaesu G-450XL Rotator Repair

Image
  Yaesu G-450XL Rotator Repair Filed in Antennas on Dec.30, 2007 In December of 2007, the rope support for the center element of my Cushcraft A3 broke, requiring me to climb the tower and bring the beam down for maintenance.  At the same time, at had been noticing that the rotator control was not indicating correctly, it was very erratic.  So I brought the rotator down for maintenance, as well. The first step was to mark the side of the case, where the top and bottom of the clam shells connected together.  This would allow me to assemble it in the correct alignment when the time came.   Marked Case of Rotator Next, I took the top cover off.  All of the bearings between the clam shells in the depression on the outside were safely stored.   Top Removed A little inspection revealed what the problem was.  The center gear had broken away from the shaft it was pressed onto.  I tried re-pressing it back onto the shaft, but it was too worn out.  I found the phone number for p
Read more

JuncTek Battery Monitor MQTT Controller

Image
 I recently installed some 48 volt Lithium Iron Phosphate battery packs at the Ranch to replace the 9 year old Lead-Acid batteries that had started to fail.   eg4-lifepower4-battery-48v-100ah   These are rack-mount battery packs that are intended for powering computer servers.  They are reported to work very well in an off-grid power system.  The Problem I had a problem to solve before the upgrade, in that the old 48 volt inverter I had been using in our solar power system required a programming interface to change its operating parameters to match the new battery specifications.  Unfortunately, the manufacturer wants over $400 for the required interface to make these changes.  I am unwilling to pay this extortion money for a simple device that should cost less than $100. The communications protocol and interface is proprietary, so it would take a considerable effort to hack the interface. There are two sets of parameters in dealing with the inverter/battery connections: 1. The chargin
Read more