Facsimile adapter unit having error detecting function

Claim 1

A facsimile adapter unit which is coupled to a host system and a line and is used for communicating between said host system and a station coupled to the line, said facsimile adapter unit comprising: decoding means for decoding image data which is transmitted from the station via the line and for outputting decoded image data; error detection means, coupled to said decoding means, for detecting an error in the decoded image data for each line; data determining means, coupled to said error detection means, for determining whether or not page image data which has image data for a plurality of lines is normal based on results obtained by said error detection means with respect to image data for the plurality of lines in the page data; first processing means, coupled to said data determining means, for sending said host system image data for each line in which no error is detected and code data corresponding to each line of image data for which the error is detected by said error detection means when said data determining means determines that the page image data is normal; second processing means, coupled to said data determining means, for sending said host system error page information including image data for each line in which no error is detected and the code data corresponding to each line of image data for which the error is detected when said data determining means determines that the page image data is not normal; and third processing means, coupled to said data determining means, for returning, to said station coupled to the line, information indicating that errors are present in image data transmitted from said station.