On an Arduino Due I've trouble to get SD card functionality (reading from/writing into files) running when running an Ethernet webserver at the same time. According to the posts in the Arduino Forum I'm not the only one which is struggling with this topic.
The reason for this is that the SD card and Ethernet is accessed via SPI. One reason for the confusion is the lack of documentation, another one are different Arduino Board versions and associated SPI Pins, and yet another one seems to be the need for potentially ethernet shield version specific patches like e.g. Ethernet_v2.h in case of this board with W5100 ethernet chip in comparison to the Ethernet Shield v2 which uses an W5500 ethernet chip.
To control the chip select signals one can use either pull-ups in HW or in SW. This should affect how one has to use the libs (SD.h, Ethernet.h)... Some interesting article of the SD lib author regarding HW considerations: https://dorkbotpdx.org/blog/paul/better_spi_bus_design_in_3_steps/
Would it be possible that you guys provide an example sketch which demonstrates the usage of SD card and Ethernet at the same time? I'm pretty sure a lot of Arduino users would appreciate this. Thanks.
On an Arduino Due I've trouble to get SD card functionality (reading from/writing into files) running when running an Ethernet webserver at the same time. According to the posts in the Arduino Forum I'm not the only one which is struggling with this topic.
The reason for this is that the SD card and Ethernet is accessed via SPI. One reason for the confusion is the lack of documentation, another one are different Arduino Board versions and associated SPI Pins, and yet another one seems to be the need for potentially ethernet shield version specific patches like e.g.
Ethernet_v2.hin case of this board with W5100 ethernet chip in comparison to the Ethernet Shield v2 which uses an W5500 ethernet chip.To control the chip select signals one can use either pull-ups in HW or in SW. This should affect how one has to use the libs (SD.h, Ethernet.h)... Some interesting article of the SD lib author regarding HW considerations: https://dorkbotpdx.org/blog/paul/better_spi_bus_design_in_3_steps/
Would it be possible that you guys provide an example sketch which demonstrates the usage of SD card and Ethernet at the same time? I'm pretty sure a lot of Arduino users would appreciate this. Thanks.