Problems about using SPI on Pixhawk

Hi, I’m currently using SPI on Pixhawk, but I encountered some problems about it.

  1. I just wanna know can I use the external SPI on board? If so, which one of the “enum AP_HAL::SPIDevice” in SPIDriver.h should I choose to initialize the device?
  2. I’ve read some code about mpu6000 and I found following ambiguous lines of code,

[color=#00BF00] /* Pin 70 defined especially to hook
up PE6 to the hal.gpio abstraction.
(It is not a valid pin under Arduino.) */[/color]
_drdy_pin = hal.gpio->channel(70);

but I found the pin70 which is PE6 is one of the external SPI pins.
Anyone has any ideas about whether MPU6000 occupies this pin?

You can look in the PX4 hardware repository on github to see the schematics.