W83877TF Datasheet, PDF (18/154 Pages) Winbond – I/O chip disk drive adapter

W83877TF
1.2 Serial Port Interface ,continued
SYMBOL PIN
I/O
SOUTB
IRTX1
43
I/O_8tc
PIRQMDS
RTSB
45
I/O_8tc
FUNCTION
UART B Serial Output. It is used to transmit serial data out to the
communication link.
During power-on reset, this pin is pulled down internally and is
defined as PIRQMDS to select the IRQ mode. While it is at
Low, IRQ pins can be set to Normal mode or IRQ sharing mode
which decided by CR18. If it is at High, the Serial IRQ mode is
selected. A 4.7 kΩ is recommended when intending to pull up at
power-on reset.
UART B Request To Send. An active low informs the modem or
data set that the controller is ready to send data.
PGOIQSEL
DTRB
IRTX2
IRRX2
During power-on reset, this pin is pulled down internally and is
defined as PGOIQSEL, which provides the power-on value for
CR16 bit 4 and bit 5 (G0IQSEL & G1IQSEL). While it is at Low,
pins 92 and 96 function as IRQ pins IRQ_B,IRQ_A respectively.
While it is at high, pins 92 and 96 function as General Purpose
I/O pins GIO0,GIO1 respectively. A 4.7 kΩ is recommended
when intends to pull up at power-on reset.
46
I/O_8tc UART B Data Terminal Ready. An active low informs the
modem or data set that the controller is ready to communicate.
95 OUT_12t Functions as a InfraRed data transmission line.
94
IN_t Functions as a InfraRed data receiving line.
1.3 Multi-Mode Parallel Port
The following pins have six functions, which are controlled by bits PRTMOD0, PRTMOD1, and
PRTMOD2 of CR0 and CR9 (refer to section 8.0, Extended Functions).
SYMBOL PIN
I/O
FUNCTION
BUSY
24
IN_t PRINTER MODE: BUSY
An active high input indicates that the printer is not ready to
receive data. This pin is pulled high internally. Refer to the
description of the parallel port for the definition of this pin in ECP
and EPP mode.
OD_{12 EXTENSION FDD MODE: MOB2}
This pin is for Extension FDD B; the function of this pin is the
same as that of the MOB pin.
OD_{12 EXTENSION 2FDD MODE: MOB2}
This pin is for Extension FDD A and B; the function of this pin is
the same as that of the MOB pin.
Publication Release Date: March 1998
-8-
Version 0.61