ST16C654CJ68 EXAR [Exar Corporation], ST16C654CJ68 Datasheet - Page 10

• Manufacturer Part Number: ST16C654CJ68
• Description: QUAD UART WITH 64-BYTE FIFO AND INFRARED (IrDA) ENCODER/DECODER
• Manufacturer: EXAR [Exar Corporation]

ST16C654/654D
SYMBOL DESCRIPTION
-TXRDY A-B
-TXRDY C-D
VCC
VCC
XTAL1
XTAL2
-CD A-B
-CD C-D
-CTS A-B
-CTS C-D
Symbol
Rev. 4.10
47,64
43,61
11,25
45,59
9,27
68
13
35
36
-
-
56,81
61,86
99,32
49,83
59,73
5,25
8,22
Pin
100
10
40
41
64,18
35,52
31,49
33,47
4,21
2,16
64
25
26
-
Signal
type
O
O
I
I
I
I
discussed in a following paragraph For 64/68 pin packages,
individual channel TX status can be read by examining
individual internal registers via -CS and A0-A4 pin func-
tions.
These outputs provide the TX FIFO/THR status for indi-
vidual transmit channels (A-D). As such, an individual
channel’s -TXRDY A-D buffer ready status is indicated by
logic 0, i.e., at least one location is empty and available in
the FIFO or THR. This pin goes to a logic 1 when there are
no more empty locations in the FIFO or THR.
Crystal or External Clock Input - Functions as a crystal input
or as an external clock input. A crystal can be connected
between this pin and XTAL2 to form an internal oscillator
circuit (see figure 8). Alternatively, an external clock can be
connected to this pin to provide custom data rates (see
Baud Rate Generator Programming and optional MIDCLK).
Output of the Crystal Oscillator or Buffered Clock - (See also
XTAL1). Crystal oscillator output or buffered clock output.
with individual UART channels A through D. A logic 0 on this
pin indicates that a carrier has been detected by the modem
for that channel.
individual UART channels, A through D. A logic 0 on the -
CTS pin indicates the modem or data set is ready to accept
transmit data from the 654. Status can be tested by reading
MSR bit-4. This pin only affects the transmit and receive
operations when Auto CTS function is enabled via the
This function is associated with 100 pin packages only.
Power supply inputs.
Carrier Detect (active low) - These inputs are associated
Clear to Send (active low) - These inputs are associated with
5-74
Pin Description