Interfacing Pixy2 with SPI with SS

[Allison]

Hello!

I am working on a project interfacing a Pixy2 with a SmartFusion development board (which has an ARM Cortex-M3 Processor). I am currently modifying the arduino code for SPI to fit the SmartFusion using the Pixy2 porting guide (https://docs.pixycam.com/wiki/doku.php?id=wiki:v2:porting_guide) and had a couple questions:

1. What exactly is the size (in bytes) of the receive packet?
2. Are the packets big or little Endian for SPI? I found this porting guide also (I think it is from the original pixy) that explicitly says that it is big endian but in the new documentation it only mentions little endian. Is this something new to the Pixy2?

Thank you in advance!

[edge]

Hello Allison,

• What exactly is the size (in bytes) of the receive packet?
• Are the packets big or little Endian for SPI? I found this porting guide also (I think it is from the original pixy) that explicitly says that it is big endian but in the new documentation it only mentions little endian. Is this something new to the Pixy2?

The integer value are all little-endian and the size of the packet varies based on the packet-type.

This document describes everything about the protocol and porting to a new controller.

https://docs.pixycam.com/wiki/doku.php?id=wiki:v2:porting_guide

Hope this helps!

Edward