GM82C803CN Datasheet, PDF (6/84 Pages) List of Unclassifed Manufacturers – 2.88 MB FDC/ Dual UARTs with FIFO/PIO(EPP/ ECP)/ IDE Interface/ S-IR/ PnP

GM82C803CN
(Continued)
PIN NO. PIN
NAME
84, 86
RI1,
RI2
BUFFER
TYPE
In
DESCRIPTION
Active low Ring Indicator inputs for the serial port. Handshake
signal which notifies the UART that the telephone ring signal is
detected by the modem. The CPU can monitor the status of RI
signal by reading bit 6 of Modem Status Register (MSR). A RI
signal state change from low to high after the last MSR read will
set MSR bit 2 to a logic ?? If bit 3 of Interrupt Enable Register is
set, the interrupt is generated when RI changes state. * Note : Bit
6 of MSR is the complement of RI.
4) PARALLEL PORT INTERFACE
73
SLCTIN _In/Out ^{Printer Select Input pin. The active low output selects the printer.}
This is the complement of bit 3 of the Parallel Control Register.
Refer to Parallel Port description for use of this pin in ECP and
EPP mode.
74
INIT
In/Out ^{Initiate pin. This output is bit 2 of the Parallel Control Register.}
This is used to initiate the printer when low.
Refer to Parallel Port description for use of this pin in ECP and
EPP mode.
76 AUTOFD ^{In/Out Autofeed pin. This output goes low to cause the printer to}
automatically feed one line after each line is printed. The
AUTOFD output is the complement of bit 1 of the Parallel Control
Register.
Refer to Parallel Port description for use of this pin in ECP and
EPP mode.
77
STROBE ^{In/Out An active low pulse on this output is used to strobe the printer data}
into the printer. The STROBE output is the complement of bit 0
of the Printer Control Register.
Refer to Parallel Port description for use of this pin in ECP and
EPP mode.
61
BUSY
In
This is a status output from the printer, a high indicating that the
printer is not ready to receive new data. Bit 7 of the Printer Status
Register is the complement of the BUSY input.
Refer to Parallel Port description for use of this pin in ECP and
EPP mode.
62
ACK
In
Acknowledge pin. A low active output from the printer indicating
that it has received the data and is ready to accept new data. Bit 6
of the Printer Status Register reads the ACK input.
60
PE
Refer to Parallel Port description for use of this pin in ECP and
EPP mode.
In
Paper End. Another status output from the printer, a high
indicating that the printer is out of paper. Bit 5 of the Printer
Status Register reads the PE input.
Refer to Parallel Port description for use of this pin in ECP and
EPP mode.