A printer may accept a print instruction; start printing of a code image on a print medium; control an operation state of the printer, wherein in a case where the printing of the code image is completed after the printing of the code image has been started, the operation state of the printer is controlled to be a respondent state, and in a case where the printing of the code image is not completed due to an error occurring after the printing of the code image has been started, the operation state of the printer is controlled to be a non-respondent state; receive an authentication request from a first external device; send the authentication response to the first external device; receive connection information from the first external device; and establish, by using the connection information, a wireless connection between the printer and a second external device.