Sparkfun Pro Micro as SPI Slave Problems

Hi, I have a Sparkfun Pro Micro (5v/16MHz) that I'm trying to use as a slave on an SPI bus. I'm using a very simple test project on the pro micro to send data to test the connection. It's roughly based off of the vanilla AVR way of doing it, in addition to a few ways that people have done it with various Arduinos.

void setup()
	pinMode(MOSI, INPUT);
	pinMode(MISO, OUTPUT);
	pinMode(SCK, INPUT);
	pinMode(SS, INPUT);

	SPCR |= _BV(SPE);

	SPDR = 0xBE;


	SPDR = 0xBE;

void loop()


I'm using a Netduino to generate clock pulses (only 200KHz, btw) to test if it's working, and I'm using a Saleae Logic analyzer to see if anything is getting spit out. From what the analyzer is telling me, the Pro Micro isn't sending my 0xBE over the MISO line (the clock/SS are going as expected). I've tried using active high AND low SS, and neither elicits a response from the Arduino.

Any help would be greatly appreciated.


How did you connect the SS pin? The Pro doesn't have it on it's headers.

Ah, nuts. I guess I just didn't do a very good job reading the schematic/accepting the transition to the 32U4 from the ATMEGA8/168/328. Looks like the SS pin is on PB0, which is the yellow RX led on the board. I should be a be able to greenwire a wire to D10 and cut the D10 trace so that SS is back where I expected it.

Ok, cut the D10 trace, and ran a wire to the correct pin on the MCU, and it works great. Thanks!

Is there anyway to re-assign/re-map the SS pin to another pin?

I dont want to cut any traces...

can I turn 8 /(SS/PCINT0)/PB0 to an output or something? and then use another pin?

I wish to use the USB Host Mini Shield with my Pro Micro's... but cant get the board to communicate to the USB Host Shield due to the SS pin not being broken out anywhere.. (and connected to an LED instead)..

I have found these two threads (but no replies for some direction)

This is more low level editing than I am used to.. so am not sure of the direction to take here?

Any advice is appreciated ... thanks!