Can anyone tell me why my output graph from CCS v5 is jagged?

Steve,

I guess I see what is happening: integers in a C6000 ISA are 32-bit values, but your graph is set to display 16-bit values. This will interleave the lower 16-bit (accurate value) with the upper 16-bit (all zero) values.

In this case, change the DSP data size to 32-bit signed integer and check if the graph improves. If you want to improve memory usage, you can also define the out_buffer array as short. Even better: include the header file <stdint.h> and define your values as uint8_t, uint16_t, uint32_t, and so on - this leaves no doubt of the integer data size across ISAs and is widely adopted across compilers (for example, check this Wikipedia entry).

Hope this helps,

Rafael