Page 1 of 4
IA8255
Advanced Information
Sheet
Programmable Peripheral Interface Adapter
Copyright
1999, InnovASIC Inc.
Customer Specific IC Solutions
FEATURES
Form, Fit, and Function Compatible with the Intel
8255A and Harris
82C55A
Packaging options available: 40 Pin Plastic DIP or 44 Pin Plastic Leaded
Chip Carrier
24 Programmable Input/Outputs
Static Read/Write or Handshaking Modes
Direct Bit Set/Reset Capability
High Speed, No "Wait State" Operation
The IA8255 uses innov
ASIC
's innovative new f
3
Program to provide industry with parts that
other vendors have declared obsolete. By specifying parts through this program a customer is
assured of never having a component become obsolete again. This advanced information sheet
assumes the original part has been designed in, and so provides a summary of capabilities only. For
new designs contact innov
ASIC
for more detailed information.
Intel is a registered trademark of Intel Corporation
Harris is a copyright trademark of Harris Corporation
Package Pinout
(6)
(1)
(2)
(3)
(4)
(5)
(7)
(8)
(9)
A0
(10)
PC7
(11)
PC6
(12)
PC5
(13)
PC4
(14)
40 Pin DIP
IA8255
D2
D3
D4
D5
(20)
PB2
(15)
PC1
(16)
PC2
(17)
PC3
(18)
PB0
(19)
PB1
(21)
(22)
(23)
(24)
PB4
PB3
(40)
(39)
(38)
(37)
(36)
(35)
(34)
(33)
(32)
(31)
(30)
(29)
(28)
(27)
(26)
(25)
PC0
PB6
PB5
VCC
PB7
D6
D7
D0
D1
WR_n
RESET
PA6
PA7
PA4
PA5
CS_n
PA3
PA2
PA1
PA0
RD_n
GND
A1
PB0
PC2
PA6
PA7
WR_n
PA5
N. C.
PA2
PB2
PB3
PB5
PB7
PB6
44 Pin LCC
IA8255
(12)
N. C.
(7)
CS_n
(8)
GND
(9)
A1
(10)
A0
(11)
PC7
(13)
PC6
(14)
PC5
(15)
PC4
(16)
PC0
(17)
PC1
RESET
D4
N. C.
D3
D1
D0
PC3
(6)
(5)
(4)
(3)
(2)
(1)
(44)
(43)
(42)
(41)
(40)
PA0
RD_n
(34)
(39)
(38)
(37)
(36)
(35)
(33)
(32)
(31)
(30)
(29)
(18)
(19)
(20)
(21)
(22)
(23)
(24)
(25)
(26)
(27)
(28)
PA4
PA3
PA1
PB1
N. C.
PB4
VCC
D7
D6
D5
D2
Page 2 of 4
IA8255
Advanced Information
Sheet
Programmable Peripheral Interface Adapter
Copyright
1999, InnovASIC Inc.
Customer Specific IC Solutions
The IA8255 is a programmable peripheral interface adapter mega-function designed to be
functionally equivalent to the Intel 8255A and Harris 82C55A devices. This function has 24 I/O
signals programmable in two groups of 12. Three modes of operation allow the following:
Basic Input/Output (Mode 0) - Port A, Port B, Port C (upper), and Port C (lower) can be
independently configured as inputs or outputs to read or hold static data. Outputs are
latched, but inputs are not latched.
Strobed Input/Output (Mode 1) - Port A and Port B can be independently configured as
strobed input or output buses. Signals from Port C are dedicated as control signals for data
handshaking.
Bidirectional Bus (Mode 2) - Port A can also be configured as a bidirectional bus, with the
majority of Port C providing the control signals. In this case, Port B is still capable of
implementing one of the previous described modes.
A block diagram is shown in Figure 1.
Functional Block Diagram
Figure 1
DATA BUS
BUFFER
GROUP A
CONTROL
GROUP B
CONTROL
8 BIT INTERNAL
DATA BUS
GROUP A
PORT A
(8)
GROUP A
PORT C
UPPER (4)
GROUP B
PORT C
LOWER
(4)
GROUP B
PORT B
(8)
CONTROL
REGISTER AND
LOGIC
A0
A1
CS_n
RESET
RD_n
WR_n
D7:D0
I/O
PA7:PA0
I/O
PC7:PC4
I/O
PC3:PC0
I/O
PB7:PB0
Page 3 of 4
IA8255
Advanced Information
Sheet
Programmable Peripheral Interface Adapter
Copyright
1999, InnovASIC Inc.
Customer Specific IC Solutions
Qualification Levels
Table 1
Part Number
Environmental/ Qual Level
IA8255-PDW40C
Commercial
IA8255-PLC44C
Commercial
IA8255-PDW40I
Industrial
IA8255-PLC44I
Industrial
The following diagram depicts the innov
ASIC
Product Identification Number.
IAXXXXX-PPPPNNNT/SP
Special Processing:
S = Space
Q = MIL-STD-883
Temperature:
C = Commercial
I = Industrial
M = Military
Number of Leads
Package Type:
Per Package Designator Table
IC Base Number
innov
ASIC
Designator
Page 4 of 4
IA8255
Advanced Information
Sheet
Programmable Peripheral Interface Adapter
Copyright
1999, InnovASIC Inc.
Customer Specific IC Solutions
Package Designator Table
Package Type
innov
ASIC
Designator
Ceramic side brazed Dual In-line
CDB
Cerdip with window
CDW
Ceramic leaded chip carrier
CLC
Cerdip without window
CD
Ceramic leadless chip carrier
CLL
PLCC
PLC
Plastic DIP standard (300 mil)
PD
Plastic DIP standard (600 mil)
PDW
Plastic metric quad flat pack
PQF
Plastic thin quad flat pack
PTQ
Skinny Cerdip
CDS
Small outline plastic gull-wing(150 mil body)
PSO
Small outline medium plastic gull-wing (207 mil body)
PSM
Small outline narrow plastic gull wing (150 mil body)
PSN
Small outline wide plastic gull wing (300 mil body)
PSW
Skinny Plastic Dip
PDS
Shrink small outline plastic (5.3mm .208 body)
PS
Thin shrink small outline plastic
PTS
Small outline large plastic gull wing (330 mil body)
PSL
Thin small outline plastic gull-wing (8 x 20mm) [TSOP]
PST
PGA
CPGA
BGA
CBGA
Contact innov
ASIC
for other package and processing options.
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