XR88C92_05 Datasheet, PDF (5/32 Pages) Exar Corporation – DUAL UNIVERSAL ASYNCHRONOUS RECEIVER AND TRANSMITTER

XR88C92/192
SYMBOL DESCRIPTION (* 44 pin LQFP)
Symbol
OP5
OP6
OP7
A0-A3
XTAL1
XTAL2
GND
-INT
IP0
IP1
IP2
Pin
Signal
44
44* type
Pin Description
16
9
O Multi-purpose output. General purpose output or one of the
following functions can be selected for this output pin by
programming the Output Port Confiuration Register bit 5;
-RxBRDY - Receive ready signal (Open drain output)
-RxBFULL - Receive FIFO full signal (Open drain output)
29
24
O Multi-purpose output. General purpose output or Transmit A
holding register empty interrupt (-TxARDY Open drain out-
put).
17
10
O Multi-purpose output. General purpose output or Transmit B
holding register empty interrupt (-TxBRDY Open drain output)
2,4,
40,42,
6,7
44,1 I Address select lines. To select internal registers.
36
30
I Crystal input 1 or external clock input. A crystal can be
connected between this pin and XTAL2 pin to utilize the
internal oscillator circuit. An external clock can be used to
clock internal circuit and baud rate generator for custom
transmission rates.
37
31
O Crystal input 2 or buffered clock output. See XTAL1.
22
16,17 Pwr Signal and power ground.
24
18
O Interrupt output (open drain, active low) This pin goes low
upon occurrence of one or more of eight maskable interrupt
conditions (when enabled by the interrupt mask register).
CPU can read the interrupt status register to determine the
interrupting condition(s). This output requires a pull-up resis-
tor.
8
2
I Multi-purpose input or Channel A Clear-To-Send (-CTSA
active low).
5
43
I Multi-purpose input or Channel B Clear-To-Send (-CTSB
active low).
40
34
I Multi-purpose input or Timer/Counter External clock input.
Rev. 1.33
5