I'm working on some code that recieves DMX-512 RS485 signals. For these purposes, a Framing Error (FE) is used to indicate the start of a packet. I'm using an RS485 decoder chip. Data is definitely coming in, but I'm having some trouble with the code. Because of the need to access the USART on a low level, I'm using direct register access to run this, but I'm having some trouble with the interrupt. Mainly that it's never being called.
Here's the code snippets of note: http://pastebin.com/GBaqNq5H
Edit to add: Ah! If I comment out the void __irq_usart3(void) ... handler function in usart.c and recompile, the program hangs as soon as the USART is initialized. Do I need to build my entire handler in usart.c ?
Edit 2: Okay. Seems like I need to somehow attach the USART3 interupt vector to __irq_usart3(void). How do I do that? =)