I want to use a Nuelectronics Ethernet shield and a SD-card library. But the libraries use the same SS pin. On this page SPI - Arduino Reference they say that I can use every pin as SS pin.
It is possible to use a pin other than pin 10 as the slave select (SS) pin. For example, the Arduino Ethernet shield uses pin 4 to control the SPI connection to the on-board SD card, and pin 10 to control the connection to the Ethernet controller.
So I tried to change the SS pin in the SDcard library to pin 3. I think that I must change something in this code:
#if defined(__AVR_ATmega8__) || \
defined(__AVR_ATmega48__) || \
defined(__AVR_ATmega88__) || \
defined(__AVR_ATmega168__)
#define configure_pin_mosi() DDRB |= (1 << DDB3)
#define configure_pin_sck() DDRB |= (1 << DDB5)
#define configure_pin_ss() DDRB |= (1 << DDB2)
#define configure_pin_miso() DDRB &= ~(1 << DDB4)
#define select_card() PORTB &= ~(1 << PB2)
#define unselect_card() PORTB |= (1 << PB2)
source: SDcard.zip sd_raw_config.h
Could someone help me?
Thanks