XR16C850CJ EXAR [Exar Corporation], XR16C850CJ Datasheet - Page 5

• Manufacturer Part Number: XR16C850CJ
• Manufacturer: EXAR [Exar Corporation]

SYMBOL DESCRIPTION
A0
A1
A2
A3 / IOR
A4
A5 / CS0
A6 / CS1
A7 / -CS2
Symbol
Rev. 1.20
40
28
27
26
22
12
13
14
-
44
31
30
29
25
12
14
15
16
Pin
48
28
27
26
20
10
11
6
9
52
31
30
29
22
10
6
9
7
Signal
type
I
I
I
I
I
I
I
I
5
Address-0 Select Bit - Internal registers address
selection in PC and STD modes.
Address-1 Select Bit Internal registers address
selection in PC and STD modes
Address-2 Select Bit Internal registers address
selection in PC and STD modes
Address-3 Select Bit or Input/Output Read (dual
function) - When the PC mode is selected, this pin
is used as 4th address line to decode the COM1-4
and LPT ports. During STD mode operation this pin
is used as Read strobe. Its function is the same as
-IOR (see -IOR), except it is active high. Either an
active -IOR or IOR is required to transfer data from
850 to CPU during a read operation. Connect this
pin to GND when –IOR is used.
Address-4 Select Bit (internal pull-up) - When the
PC mode is selected, this pin is used as 5th address
line to decode the COM1-4 and LPT ports. This pin
has no function in the STD mode.
Address-5 Select Bit or Chip Select-0 (dual function)
- When the PC mode is selected, this pin is used as
6th address line to decode the COM1-4 and LPT
ports. During STD mode a logical 1 on this pin
provides the chip select 0 function. Connect this pin
to VCC when CS1 or –CS2 is used.
Address-6 Select Bit or Chip Select-1 (dual function)
- When the PC mode is selected, this pin is used as
7th address line to decode the COM1-4 and LPT
ports. During STD mode a logical 1 on this pin
provides the chip select 1 function. Connect this pin
to VCC when CS0 or –CS2 is used.
Address-7 Select Bit or Chip Select -2 (dual func-
tion) - When the PC mode is selected, this pin is
used as 8th address line to decode the COM1-4 and
LPT ports. During STD mode a logical 1 on this pin
provides the chip select 2 function. Connect this pin
Pin Description
XR16C850