Specifications

Serial Communications (82050)
Modem Control
The Modem Control block includes the serial communication
handshake, RS-485 buffer control, and parallel port enable signals.
The serial handshake signals output by this control block are Request
to Send (RTS) and Data Terminal Ready (DTR). The DTR signal also
serves as an enable for the Transmit Data and Request To Send
drivers when the ACC is configured for RS-485 operation. Both the
RTS and DTR signals are programmable through the Modem Control
register. The serial handshake signals monitored by this control block
are Clear to Send (CTS), Data Set Ready (DSR), Data Carrier Detect
(DCD), and Ring Indicator (RI). These signals are monitored through
the Modem Status register. The remaining OUT2 signal is pro-
grammable through the Modem Control register to enable and disable
the 24 bits of parallel I/O on the ZT 8832.
Interrupt Contr
ol
The ACC includes a fully prioritized interrupt system to monitor and
report operating conditions such as receiver data available and
transmitter empty, and error conditions such as overrun, parity,
framing, and break. The Interrupt Control block monitors the interrupt
sources defined by the Interrupt Enable register and reports any active
interrupts through the Interrupt Identify register.
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