$DE0E/56846/RR+14:  SilverSurfer: Modem Status Register (read only)

   +-------+--------------------------------------------------------+
   | Bit 7 |   1 = DCD  (Data Carrier Detect)                       |
   | Bit 6 |   1 = RI   (Ring Indicator)                            |
   | Bit 5 |   1 = DSR  (Data Set Ready)                            |
   | Bit 4 |   1 = CTS  (Clear To Send)                             |
   | Bit 3 |   1 = DDCD (Delta Data Carrier Detect = DCD changed)   |
   | Bit 2 |   1 = TERI (Ring Indicator changed)                    |
   | Bit 1 |   1 = DDSR (Delta DSR = DSR changed)                   |
   | Bit 0 |   1 = DCTS (Delta CTS = CTS changed)                   |
   +-------+--------------------------------------------------------+
   Bits 0-3 are reset when read.
   Bit 4 is the $DE0C's RTS during loopback test.
   Bit 5 is the $DE0C's DTR during loopback test.
   Bit 6 is the $DE0C's OUT1 during loopback test.
   Bit 7 is the $DE0C's OUT2 during loopback test.