A page printer comprising: a memory containing a buffer; an image output section for forming an image based on data and outputting the image; a reception section for writing data received from a host into the buffer; a transfer section for transferring the data in the buffer to said image output section; an error detection section for detecting an underrun error caused by a fact that a read address of said transfer section from the buffer catches up with a write address of said reception section into the buffer; and an error notification section for notifying the host of occurrence of the underrun error to cause the host to resend the data under a condition where the underrun error is harder to occur when the underrun error is detected.
