struct dzdevice
{
short dzcsr; /* control-status register */
short dzrbuf; /* receiver buffer register (read only) */
#define dzlpr dzrbuf /* line parameter register (write only) */
char dztcr; /* transmitter control register */
char dzdtr; /* data terminal ready register */
char dztbuf; /* transmitter buffer (write only) */
#define dzring dztbuf; /* ring register (read only) */
char dzbrk; /* break register (write only) */
#define dzcar dzbrk /* carrier register (read only) */
};
/* Bits in dzcsr */
#define DZ_MM 0000010 /* Maintenance mode */
#define DZ_CLR 0000020 /* Clear */
#define DZ_MSE 0000040 /* Master Scan Enable */
#define DZ_RIE 0000100 /* Receiver Interrupt Enable */
#define DZ_RDO 0000200 /* Receiver Done (read only) */
#define DZ_SAE 0010000 /* Silo Alarm Enable (read/write) */
#define DZ_SA 0020000 /* Silo Alarm Enable (read only) */
#define DZ_TIE 0040000 /* Transmit Interrupt Enable */
#define DZ_TRDY 0100000 /* Transmitter Ready (read only) */
#ifdef DZ_SILO
#define DZ_IEN (DZ_MSE|DZ_RIE|DZ_TIE|DZ_SAE)
#else
#define DZ_IEN (DZ_MSE|DZ_RIE|DZ_TIE)
#endif
/* Bits in dzlpr */
#define BITS7 020
#define BITS8 030
#define TWOSB 040
#define PENABLE 0100
#define OPAR 0200
/* Bits in dzrbuf */
#define DZ_PE 010000 /* parity error */
#define DZ_FE 020000 /* framing error */
#define DZ_DO 040000 /* overrun */
/* Flags for modem control */
#define DZ_ON 1
#define DZ_OFF 0