A method comprising: receiving, at a surface location, a signal wirelessly transmitted at a first frequency from a downhole controller (250, 400) disposed within a wellbore; demodulating the received signal to a demodulated digital value; adding the demodulated value to an end of a buffer string; processing the buffer string to determine whether the buffer string contains a message that is valid, wherein processing the buffer string to determine whether the buffer string contains a message that is valid comprises extracting a cyclic redundancy check field string and an auxiliary field string from the buffer string, determining that the auxiliary field string translates to a first valid state of a plurality of valid states, wherein the valid states are states of downhole equipment encountered in well operations, in response to determining that the auxiliary field string translates to the first valid state, determining a respective, predetermined bit string length associated with the first valid state, in response to determining the respective, predetermined bit string length associated with the first valid state, calculating a checksum of a portion of the buffer string having the respective, predetermined bit string length associated with the first valid state, and determining that the calculated checksum matches the cyclic redundancy check field string; and in response to determining that the buffer string contains the message that is valid, decoding the message. receiving, at a surface location, a signal wirelessly transmitted at a first frequency from a downhole controller (250, 400) disposed within a wellbore; demodulating the received signal to a demodulated digital value; adding the demodulated value to an end of a buffer string; processing the buffer string to determine whether the buffer string contains a message that is valid, wherein processing the buffer string to determine whether the buffer string contains a message that is valid comprises extracting a cyclic redundancy check field string and an auxiliary field string from the buffer string, determining that the auxiliary field string translates to a first valid state of a plurality of valid states, wherein the valid states are states of downhole equipment encountered in well operations, in response to determining that the auxiliary field string translates to the first valid state, determining a respective, predetermined bit string length associated with the first valid state, in response to determining the respective, predetermined bit string length associated with the first valid state, calculating a checksum of a portion of the buffer string having the respective, predetermined bit string length associated with the first valid state, and determining that the calculated checksum matches the cyclic redundancy check field string; and extracting a cyclic redundancy check field string and an auxiliary field string from the buffer string, determining that the auxiliary field string translates to a first valid state of a plurality of valid states, wherein the valid states are states of downhole equipment encountered in well operations, in response to determining that the auxiliary field string translates to the first valid state, determining a respective, predetermined bit string length associated with the first valid state, in response to determining the respective, predetermined bit string length associated with the first valid state, calculating a checksum of a portion of the buffer string having the respective, predetermined bit string length associated with the first valid state, and determining that the calculated checksum matches the cyclic redundancy check field string; and in response to determining that the buffer string contains the message that is valid, decoding the message.