`define CONTROL_LOOP_NOOP 0
`define CONTROL_LOOP_STATUS 1
`define CONTROL_LOOP_SETPT 2
`define CONTROL_LOOP_P 3
`define CONTROL_LOOP_ALPHA 4
`define CONTROL_LOOP_ERR 5
`define CONTROL_LOOP_ADJ 5
`define CONTROL_LOOP_WRITE_BIT (1 << (CONTROL_LOOP_CMD_WIDTH-1))
`define CONTROL_LOOP_CMD_WIDTH 8