1.  Field of the Invention
The present invention relates to a digital signal recording medium cassette for use on a video tape recorder (hereinafter referred to as VTR) or a video cassette recorder (hereinafter referred to as VCR), a recording/reproducing apparatus to be connected thereto, and a remote commander apparatus to be connected thereto.  More specifically, the present invention relates to a recording medium cassette, a recording/reproducing apparatus to be connected thereto, and a remote commander apparatus to be connected thereto, each capable of displaying specific pieces of information about the recording medium cassette. 
2.  Description of the Prior Art
As is known, specific pieces of information about a recording medium cassette for use on a VTR or VCR including the length, type, grade, and available remaining capacity of a tape accommodated in the cassette, whether the tape is recorded or blank, and whether the tape is a rental video tape or not are necessary for protecting recorded data from destruction, ensuring proper recording, and recording the number of dubbing times to prevent illegal use. 
Accordingly, these specific pieces of information are written beforehand in a specific area of the tape, such as a subcode area.  When recording or reproduction of a cassette tape has been completed or when it has been unloaded from a VTR or a VCR, the written information is changed or a new piece of information is added to it.  Some recording medium cassettes are provided with recognition holes for reading these pieces of information, on the back of their body generally at lower right and left corners. 
Recognition as referred to herein denotes a function provided by bottom side b of recording medium cassette A as shown in FIG.  17 for example.  A plurality of recognition holes c formed on the bottom side b in each lower corner thereof represent the type, quality, and other information about the recording medium cassette A.
The plurality of recognition holes c are each assigned with a specific piece of information to be displayed.  For example, one of recognition holes c represents a magnetic tape type while another represents a magnetic tape thickness. 
When the recording medium cassette A is loaded into a recording/reproducing apparatus, a pin of a detection switch provided on the apparatus gets into a corresponding recognition hole c to detect a piece of information assigned thereto based on a depth thereof.  In FIG.  17, indicated by d is a cassette positioning hole. 
In another approach, specific pieces of information about a recording medium cassette including its magnetic tape type, whether it has been recorded or blank, and whether it is a rental video cassette or not are stored beforehand in a memory device provided on the cassette having no above-mentioned recognition holes.  This proposition is found in: U.S. Pat.  No.  4,338,644 Jul. 6, 1982, Theophiel C. J. L. Starr; U.S. Pat.  No.  4,383,285 May 10, 1983, Theophiel C. J. L. Starr; U.S. Pat.  No.  4,426,684 Jan. 17, 1984, Claude Sechet, et al.;  and U.S. Pat.  No.  4,839,875 Jun. 13, 1989, Zenkichi Kuriyama, et al. 
The problem with the above-mentioned prior art techniques is that the information recorded on the recording medium cassette cannot be known before it has been set in a recording/reproducing apparatus and the magnetic tape of the cassette has been fully loaded in the apparatus, making it extremely difficult to check or manage the informational content of a lot of cassettes in a short time after such an activity is initiated. 
Accordingly, some means are required so that the recording information can be known at least before the cassette is loaded in the recording/reproducing apparatus.