Intel EG87C42 Universal peripheral interface chmos 8-bit slave microcontroller Datasheet

UPI-C42/UPI-L42
UNIVERSAL PERIPHERAL INTERFACE
CHMOS 8-BIT SLAVE MICROCONTROLLER
Y
Y
Y
Y
Y
Y
Y
Y
Pin, Software and Architecturally
Compatible with all UPI-41 and UPI-42
Products
Low Voltage Operation with the UPIL42
Ð Full 3.3V Support
Hardware A20 Gate Support
Suspend Power Down Mode
Security Bit Code Protection Support
8-Bit CPU plus ROM/OTP EPROM, RAM,
I/O, Timer/Counter and Clock in a
Single Package
4096 x 8 ROM/OTP, 256 x 8 RAM 8-Bit
Timer/Counter, 18 Programmable I/O
Pins
DMA, Interrupt, or Polled Operation
Supported
Y
Y
Y
Y
Y
Y
Y
Y
One 8-Bit Status and Two Data
Registers for Asynchronous Slave-toMaster Interface
Fully Compatible with all Intel and Most
Other Microprocessor Families
Interchangeable ROM and OTP EPROM
Versions
Expandable I/O
Sync Mode Available
Over 90 Instructions: 70% Single Byte
Quick Pulse Programming Algorithm
Ð Fast OTP Programming
Available in 40-Lead Plastic, 44-Lead
Plastic Leaded Chip Carrier, and
44-Lead Quad Flat Pack Packages
(See Packaging Spec., Order Ý240800, Package Type P, N,
and S)
The UPI-C42 is an enhanced CHMOS version of the industry standard Intel UPI-42 family. It is fabricated on
Intel’s CHMOS III-E process. The UPI-C42 is pin, software, and architecturally compatible with the NMOS UPI
family. The UPI-C42 has all of the same features of the NMOS family plus a larger user programmable memory
array (4K), hardware A20 gate support, and lower power consumption inherent to a CHMOS product.
The UPI-L42 offers the same functionality and socket compatibility as the UPI-C42 as well as providing low
voltage 3.3V operation.
The UPI-C42 is essentially a ‘‘slave’’ microcontroller, or a microcontroller with a slave interface included on the
chip. Interface registers are included to enable the UPI device to function as a slave peripheral controller in the
MCS Modules and iAPX family, as well as other 8-, 16-, and 32-bit systems.
To allow full user flexibility, the program memory is available in ROM and One-Time Programmable EPROM
(OTP).
290414 – 1
Figure 1. DIP Pin
Configuration
290414 – 2
Figure 2. PLCC Pin Configuration
290414 – 3
Figure 3. QFP Pin Configuration
*Other brands and names are the property of their respective owners.
Information in this document is provided in connection with Intel products. Intel assumes no liability whatsoever, including infringement of any patent or
copyright, for sale and use of Intel products except as provided in Intel’s Terms and Conditions of Sale for such products. Intel retains the right to make
changes to these specifications at any time, without notice. Microcomputer Products may have minor variations to this specification known as errata.
COPYRIGHT © INTEL CORPORATION, 1996
December 1995
Order Number: 290414-003
UPI-C42/UPI-L42
Table 1. Pin Description
Symbol
DIP
Pin
No.
PLCC
Pin
No.
QFP
Pin
No.
TEST 0,
TEST 1
1
39
2
43
18
16
Type
I
Name and Function
TEST INPUTS: Input pins which can be directly tested using conditional
branch instructions.
FREQUENCY REFERENCE: TEST 1 (T1) functions as the event timer
input (under software control). TEST 0 (T0) is a multi-function pin used
during PROM programming and ROM/EPROM verification, during Sync
Mode to reset the instruction state to S1 and synchronize the internal clock
to PH1.
XTAL 1
2
3
19
O
OUTPUT: Output from the oscillator amplifier.
XTAL 2
3
4
20
I
INPUT: Input to the oscillator amplifier and internal clock generator
circuits.
RESET
4
5
22
I
RESET: Input used to reset status flip-flops, set the program counter to
zero, and force the UPI-C42 from the suspend power down mode.
RESET is also used during EPROM programming and verification.
SS
5
6
23
I
SINGLE STEP: Single step input used in conjunction with the SYNC output
to step the program through each instruction (EPROM). This should be tied
to a 5V when not used. This pin is also used to put the device in Sync
Mode by applying 12.5V to it.
CS
6
7
24
I
CHIP SELECT: Chip select input used to select one UPI microcomputer
out of several connected to a common data bus.
EA
7
8
25
I
EXTERNAL ACCESS: External access input which allows emulation,
testing and ROM/EPROM verification. This pin should be tied low if
unused.
RD
8
9
26
I
READ: I/O read input which enables the master CPU to read data and
status words from the OUTPUT DATA BUS BUFFER or status register.
A0
9
10
27
I
COMMAND/DATA SELECT: Address Input used by the master processor
to indicate whether byte transfer is data (A0 e 0, F1 is reset) or command
(A0 e 1, F1 is set). A0 e 0 during program and verify operations.
WR
10
11
28
I
WRITE: I/O write input which enables the master CPU to write data and
command words to the UPI INPUT DATA BUS BUFFER.
SYNC
11
13
29
O
OUTPUT CLOCK: Output signal which occurs once per UPI instruction
cycle. SYNC can be used as a strobe for external circuitry; it is also used to
synchronize single step operation.
D0 – D7
(BUS)
12– 19
14– 21
30– 37
I/O
DATA BUS: Three-state, bidirectional DATA BUS BUFFER lines used to
interface the UPI microcomputer to an 8-bit master system data bus.
P10 – P17
27– 34
30– 33
35– 38
2 – 10
I/O
PORT 1: 8-bit, PORT 1 quasi-bidirectional I/O lines. P10 –P17 access the
signature row and security bit.
2
UPI-C42/UPI-L42
Table 1. Pin Description (Continued)
DIP
Pin
No.
PLCC
Pin
No.
QFP
Pin
No.
21– 24
35– 38
24– 27
39– 42
PROG
25
VCC
Symbol
Type
Name and Function
39– 42
11, 13– 15
I/O
PORT 2: 8-bit, PORT 2 quasi-bidirectional I/O lines. The lower 4 bits
(P20 –P23) interface directly to the 8243 I/O expander device and
contain address and data information during PORT 4 – 7 access. P21
can be programmed to provide hardware A20 gate support. The upper
4 bits (P24 –P27) can be programmed to provide interrupt Request and
DMA Handshake capability. Software control can configure P24 as
Output Buffer Full (OBF) interrupt, P25 as Input Buffer Full (IBF)
interrupt, P26 as DMA Request (DRQ), and P27 as DMA ACKnowledge
(DACK).
28
43
I/O
PROGRAM: Multifunction pin used as the program pulse input during
PROM programming.
During I/O expander access the PROG pin acts as an address/data
strobe to the 8243. This pin should be tied high if unused.
40
44
17
POWER: a 5V main power supply pin.
VDD
26
29
1
POWER: a 5V during normal operation. a 12.75V during programming
operation. Low power standby supply pin.
VSS
20
22
38
GROUND: Circuit ground potential.
P20 – P27
290414 – 4
Figure 4. Block Diagram
3
UPI-C42/UPI-L42
UPI-C42/L42 PRODUCT SELECTION GUIDE
UPI-C42: Low power CHMOS version of the UPI-42.
Device
Package
80C42
N, P S
82C42PC
82C42PD
82C42PE
N, P, S
N, P, S
N, P, S
87C42
N, P, S
ROM
OTP
4K
Comments
ROM Device
Phoenix MultiKey/42 firmware, PS/2 style mouse support
Phoenix MultiKey/42L firmware, KBC and SCC for portable apps.
Phoenix MultiKey/42G firmware, Energy Efficient KBC solution
4K
One Time Programmable Version
UPI-L42: The low voltage 3.3V version of the UPI-C42.
Device
Package
80L42
N, P S
82L42PC
82L42PD
N, P, S
N, P, S
87L42
N, P, S
ROM
OTP
4K
Comments
ROM Device
Phoenix MultiKey/42 firmware, PS/2 style mouse support
Phoenix MultiKey/42L firmware, KBC and SCC for portable apps.
4K
One Time Programmable Version
N e 44 lead PLCC, P e 40 lead PDIP, S e 44 lead QFP, D e 40 lead CERDIP
KBC e Key Board Control, SCC e Scan Code Control
THE INTEL 82C42
As shown in the UPI-C42 product matrix, the UPIC42 is offered as a pre-programmed 80C42 with various versions of MultiKey/42 keyboard controller
firmware developed by Phoenix Technologies Ltd.
4
The 82C42PC provides a low powered solution for
industry standard keyboard and PS/2 style mouse
control. The 82C42PD provides a cost effective
means for keyboard and scan code control for notebook platforms. The 82C42PE allows a quick time to
market, low cost solution for energy efficient desktop designs.
UPI-C42/UPI-L42
UPI-42 COMPATIBLE FEATURES
1. Two Data Bus Buffers, one for input and one for
output. This allows a much cleaner Master/Slave
protocol.
290414 – 5
4. P24 and P25 are port pins or Buffer Flag pins
which can be used to interrupt a master processor. These pins default to port pins on Reset.
If the ‘‘EN FLAGS’’ instruction has been executed, P24 becomes the OBF (Output Buffer Full)
pin. A ‘‘1’’ written to P24 enables the OBF pin (the
pin outputs the OBF Status Bit). A ‘‘0’’ written to
P24 disables the OBF pin (the pin remains low).
This pin can be used to indicate that valid data is
available from the UPI (in Output Data Bus Buffer).
If ‘‘EN FLAGS’’ has been executed, P25 becomes the IBF (Input Buffer Full) pin. A ‘‘1’’ written to P25 enables the IBF pin (the pin outputs
the inverse of the IBF Status Bit. A ‘‘0’’ written to
P25 disables the IBF pin (the pin remains low).
This pin can be used to indicate that the UPI is
ready for data.
2. 8 Bits of Status
ST7 ST6 ST5 ST4 F1 F0 IBF OBF
Data Bus Buffer Interrupt Capability
D7 D6 D5 D4 D3 D2 D1 D0
ST4 –ST7 are user definable status bits. These
bits are defined by the ‘‘MOV STS, A’’ single
byte, single cycle instruction. Bits 4–7 of the
acccumulator are moved to bits 4–7 of the status
register. Bits 0–3 of the status register are not
affected.
MOV STS, A
1
D7
0
290414 – 7
Op Code: 90H
0
1
0
0
0
0
D0
3. RD and WR are edge triggered. IBF, OBF, F1 and
INT change internally after the trailing edge of RD
or WR.
During the time that the host CPU is reading the
status register, the UPI is prevented from updating this register or is ‘locked out.’
EN FLAGS
1
1
Op Code: 0F5H
1
1
0
1
0
D7
1
D0
5. P26 and P27 are port pins or DMA handshake
pins for use with a DMA controller. These pins
default to port pins on Reset.
If the ‘‘EN DMA’’ instruction has been executed,
P26 becomes the DRQ (DMA Request) pin. A ‘‘1’’
written to P26 causes a DMA request (DRQ is
activated). DRQ is deactivated by DACK # RD,
DACK # WR, or execution of the ‘‘EN DMA’’ instruction.
290414 – 6
DMA Handshake Capability
290414 – 8
5
UPI-C42/UPI-L42
If ‘‘EN DMA’’ has been executed, P27 becomes
the DACK (DMA ACKnowledge) pin. This pin acts
as a chip select input for the Data Bus Buffer
registers during DMA transfers.
EN DMA
1
Op Code: 0E5H
1
1
0
0
1
0
1
D7
D0
6. When EA is enabled on the UPI, the program
counter is placed on Port 1 and the lower four
bits of Port 2 (MSB e P23, LSB e P10). On the
UPI this information is multiplexed with PORT
DATA (see port timing diagrams at end of this
data sheet).
7. The UPI-C42 supports the Quick Pulse Programming Algorithm, but can also be programmed
with the Intelligent Programming Algorithm. (See
the Programming Section.)
PROGRAM MEMORY BANK SWITCH
The switching of 2K program memory banks is accomplished by directly setting or resetting the most
significant bit of the program counter (bit 11); see
Figure 5. Bit 11 is not altered by normal incrementing of the program counter, but is loaded with the
contents of a special flip-flop each time a JMP or
CALL instruction is executed. This special flip-flop is
set by executing an SEL PMB1 instruction and reset
by SEL PMB0. Therefore, the SEL PMB instruction
may be executed at any time prior to the actual bank
switch which occurs during the next branch instruction encountered. Since all twelve bits of the program counter, including bit 11, are stored in the
stack, when a Call is executed, the user may jump to
subroutines across the 2K boundary and the proper
PC will be restored upon return. However, the bank
switch flip-flop will not be altered on return.
UPI-C42 FEATURES
Programmable Memory Size Increase
The user programmable memory on the UPI-C42 will
be increased from the 2K available in the NMOS
product by 2X to 4K. The larger user programmable
memory array will allow the user to develop more
complex peripheral control micro-code. P2.3 (port 2
bit 3) has been designated as the extra address pin
required to support the programming of the extra 2K
of user programmable memory.
The new instruction SEL PMB1 (73h) allows for access to the upper 2K bank (locations 2048–4095).
The additional memory is completely transparent to
users not wishing to take advantage of the extra
memory space. No new commands are required to
access the lower 2K bytes. The SEL PMB0 (63h)
has also been added to the UPI-C42 instruction set
to allow for switching between memory banks.
Extended Memory Program
Addressing (Beyond 2K)
For programs of 2K words or less, the UPI-C42 addresses program memory in the conventional manner. Addresses beyond 2047 can be reached by executing a program memory bank switch instruction
(SEL PMB0, SEL PMB1) followed by a branch instruction (JMP or CALL). The bank switch feature
extends the range of branch instructions beyond
their normal 2K range and at the same time prevents
the user from inadvertently crossing the 2K boundary.
6
290414 – 30
Figure 5. Program Counter
INTERRUPT ROUTINES
Interrupts always vector the program counter to location 3 or 7 in the first 2K bank, and bit 11 of the
program counter is held at ‘‘0’’ during the interrupt
service routine. The end of the service routine is signaled by the execution of an RETR instruction. Interrupt service routines should therefore be contained
entirely in the lower 2K words of program memory.
The execution of a SEL PMB0 or SEL PMB1 instruction within an interrupt routine is not recommended
since it will not alter PC11 while in the routine, but
will change the internal flip-flop.
Hardware A20 Gate Support
This feature has been provided to enhance the performance of the UPI-C42 when being used in a keyboard controller application. The UPI-C42 design
has included on chip logic to support a hardware
GATEA20 feature which eliminates the need to provide firmware to process A20 command sequences,
UPI-C42/UPI-L42
thereby providing additional user programmable
memory space. This feature is enabled by the
A20EN instruction and remains enabled until the device is reset. It is important to note that the execution of the A20EN instruction redefines Port 2, bit 1
as a pure output pin with read only characteristics.
The state of this pin can be modified only through a
valid ‘‘D1’’ command sequence (see Table 1). Once
enabled, the A20 logic will process a ‘‘D1’’ command sequence (write to output port) by setting/resetting the A20 bit on port 2, bit 1 (P2.1) without
requiring service from the internal CPU. The host
can directly control the status of the A20 bit. At no
time during this host interface transaction will the
IBF flag in the status register be activated. Table 1
gives several possible GATEA20 command/data sequences and UPI-C42 responses.
Table 1. D1 Command Sequences
A0 R/W DB Pins IBF A20
Comments
SUSPEND
The execution of the suspend instruction (82h or
E2h) causes the UPI-C42 to enter the suspend
mode. In this mode of operation the oscillator is not
running and the internal CPU operation is stopped.
The UPI-C42 consumes s 40 mA in the suspend
mode. This mode can only be exited by RESET.
CPU operation will begin from PC e 000h when the
UPI-C42 exits from the suspend power down mode.
Suspend Mode Summary
#
#
#
#
#
Oscillator Not Running
CPU Operation Stopped
Ports Tristated with Weak ( E 2–10 mA) Pull-Up
Micropower Mode (ICC s 40 mA)
This mode is exited by RESET
n(1) Set A20 Sequence
1 Only DB1 Is Processed
n
1
0
1
W
W
W
D1h
DFh
FFH(2)
0
0
0
1
0
1
W
W
W
D1h
DDh
FFh
0
0
0
n
0
n
Clear A20 Sequence
1
1
0
1
W
W
W
W
D1h
D1h
DFh
FFh
0
0
0
0
n
n
1
n
Double Trigger Set
Sequence
1
1
0
W
W
W
D1h
XXh(3)
DDh
0
1
1
n
n
n
Invalid Sequence
No Change in State
of A20 Bit
NOTES:
1. Indicates that P2.1 remains at the previous logic level.
2. Only FFh commands in a valid A20 sequence have no
effect on IBF. An FFh issued at any other time will activate
IBF.
3. Any command except D1.
The above sequences assume that the GATEA20
logic has been enabled via the A20EN instruction.
As noted, only the value on DB 1 (data bus, bit 1) is
processed. This bit will be directly passed through to
P2.1 (port 2, bit 1).
7
UPI-C42/UPI-L42
Table 2 covers all suspend mode pin states. In addition to the suspend power down mode, the UPI-C42
will also support the NMOS power down mode as
outlined in Chapter 4 of the UPI-42AH users manual.
Tristate
Weak Pull-Up
Disabled
The UPI-C42 will support several new instructions to
allow for the use of new C42 features. These instructions are not necessary to the user who does
not wish to take advantage of any new C42 functionality. The C42 will be completely compatible with all
current NMOS code/applications. In order to use
new features, however, some code modifications will
be necessary. All new instructions can easily be inserted into existing code by use of the ASM-48 macro facility as shown in the following example:
Normal
Normal
Macname MACRO
DB 63H
ENDM
Table 2. Suspend Mode Pin States
Pins
Ports 1 and 2
Outputs
Inputs
DBB(1)
Outputs
Inputs
NEW UPI-C42 INSTRUCTIONS
Suspend
System Control
(RDÝ, WRÝ,
CSÝ, A0)
Disabled
ResetÝ
Enabled
Crystal Osc.
(XTAL1, XTAL2)
Disabled
New Instructions
The following is a list of additions to the UPI-42 instruction set. These instructions apply only to the
UPI-C42. These instructions must be added to existing code in order to use any new functionality.
Test 0, Test 1
Disabled
Prog
High
Sync
High
EA
Disabled,
No Pull-Up
PC Bit 11 is set to zero on next JMP or CALL instruction. All references to program memory fall within
the range of 0 – 2047 (0 – 7FFh).
SSÝ
Disabled,
Weak Pull-Up
SEL PMB1 Select Program Memory Bank 1
k 40 mA
OPCODE
ICC
NOTES:
1. DBB outputs are Tristate unless CSÝ and RDÝ are active. DBB inputs are disabled unless CSÝ and WRÝ are
active.
2. A ‘‘disabled’’ input will not cause current to be drawn
regardless of input level (within the supply range).
3. Weak pull-ups have current capability of typically 5 mA.
SEL PMB0 Select Program Memory Bank 0
OPCODE
0110 0011 (63h)
0111 0011 (73h)
PC Bit 11 is set to one on next JMP or CALL instruction. All references to program memory fall within
the range of 2048 – 4095 (800h – FFFh).
ENA20 Enables Auto A20 hardware
OPCODE
0011 0011 (33h)
Enables on chip logic to support Hardware A20 Gate
feature. Will remain enabled until device is reset.
8
UPI-C42/UPI-L42
This circuitry gives the host direct control of port 2
bit 1 (P2.1) without intervention by the internal CPU.
When this opcode is executed, P2.1 becomes a dedicated output pin. The status of this pin is read-able
but can only be altered through a valid ‘‘D1’’ command sequence (see Table 1).
XTAL 2
Clock Input
Reset
Initialization and Address Latching
Test 0
Selection of Program or Verify Mode
SUSPEND Invoke Suspend Power Down Mode
EA
Activation of Program/Verify Signature
Row/Security Bit Modes
OPCODE
(E2h)
BUS
Address and Data Input
Data Output During Verify
P20–23
Address Input
1000 0010 (82h) or 1110 0010
Enables device to enter micro power mode. In this
mode the external oscillator is off, CPU operation is
stopped, and the Port pins are tristated. This mode
can only be exited via a RESET signal.
PROGRAMMING AND VERIFYING THE
UPI-C42
The UPI-C42 programming will differ from the NMOS
device in three ways. First, the C42 will have a 4K
user programmable array. The UPI-C42 will also be
programmed using the Intel Quick-Pulse Programming Algorithm. Finally, port 2 bit three (P2.3) will be
used during program as the extra address pin required to program the upper 2K bank of additional
memory. None of these differences have any effect
on the full CHMOS to NMOS device compatibility.
The extra memory is fully transparent to the user
who does not need, or want, to use the extra memory space of the UPI-C42.
In brief, the programming process consists of: activating the program mode, applying an address,
latching the address, applying data, and applying a
programming pulse. Each word is programmed completely before moving on to the next and is followed
by a verification step. The following is a list of the
pins used for programming and a description of their
functions:
Pin
Function
VDD
Programming Power Supply
PROG
Program Pulse Input
WARNING
An attempt to program a missocketed UPI-C42 will result in
severe damage to the part. An indication of a properly
socketed part is the appearance of the SYNC clock output.
The lack of this clock may be used to disable the programmer.
The Program/Verify sequence is:
1. Insert 87C42 in programming socket
2. CS e 5V, VCC e 5V, VDD e 5V, RESET e 0V,
A0 e 0V, TEST 0 e 5V, clock applied or internal oscillator operating, BUS floating, PROG e
5V.
3. TEST 0 e 0V (select program mode)
4. EA e 12.75V (active program mode)
5. VCC e 6.25V (programming supply)
6. VDD e 12.75V (programming power)
7. Address applied to BUS and P20–23
8. RESET e 5V (latch address)
9. Data applied to BUS
10. PROG e 5V followed by one 100 ms pulse to
0V
11. TEST 0 e 5V (verify mode)
12. Read and verify data on BUS
13. TEST 0 e 0V
14. RESET e 0V and repeat from step 6
15. Programmer should be at conditions of step 1
when the 87C42 is removed from socket
Please follow the Quick-Pulse Programming flow
chart for proper programming procedure shown in
Figure 6.
9
UPI-C42/UPI-L42
flow chart of the Quick-Pulse Programming Algorithm is shown in Figure 6.
The entire sequence of program pulses and byte
verifications is performed at VCC e 6.25V and
VDD e 12.75V. When programming has been completed, all bytes should be compared to the original
data with VCC e VDD e 5V.
A verify should be performed on the programmed
bits to ensure that they have been correctly programmed. The verify is performed with T0 e 5V,
VDD e 5V, EA e 12.75V, SSÝ e 5V, PROG e 5V,
A0 e 0V, and CSÝ e 5V.
In addition to the Quick-Pulse Programming Algorithm, the UPI-C42 OPT is also compatible with Intel’s Inteligent Programming Algorithm which is used
to program the NMOS UPI-42AH OTP devices.
The entire sequence of program pulses and byte
verifications is performed at VCC e 6.25V and
VDD e 12.75V. When the inteligent Programming
cycle has been completed, all bytes should be compared to the original data with VCC e 5.0, VDD e
5V.
Verify
A verify should be performed on the programmed
bits to determine that they have been correctly programmed. The verify is performed with T0 e 5V,
VDD e 5V, EA e 12.75V, SS e 5V, PROG e 5V,
A0 e 0V, and CS e 5V.
SECURITY BIT
290414 – 14
Figure 6. Quick-Pulse Programming Algorithm
Quick-Pulse Programming Algorithm
As previously stated, the UPI-C42 will be programmed using the Quick-Pulse Programming Algorithm, developed by Intel to substantially reduce the
thorughput time in production programming.
The Quick-Pulse Programming Algorithm uses initial
pulses of 100 ms followed by a byte verification to
determine when the address byte has been successfully programmed. Up to 25 100 ms pulses per
byte are provided before a failure is recognized. A
10
The security bit is a single EPROM cell outside the
EPROM array. The user can program this bit with the
appropriate access code and the normal programming procedure, to inhibit any external access to the
EPROM contents. Thus the user’s resident program
is protected. There is no direct external access to
this bit. However, the security byte in the signature
row has the same address and can be used to
check indirectly whether the security bit has been
programmed or not. The security bit has no effect on
the signature mode, so the security byte can always
be examined.
SECURITY BIT PROGRAMMING/
VERIFICATION
Programming
a. Read the security byte of the signature mode.
Make sure it is 00H.
UPI-C42/UPI-L42
b. Apply access code to appropriate inputs to put
the device into security mode.
c. Apply high voltage to EA and VDD pins.
d. Follow the programming procedure as per the
Quick-Pulse Programming Algorithm with known
data on the databus. Not only the security bit, but
also the security byte of the signature row is programmed.
e. Verify that the security byte of the signature
mode contains the same data as appeared on
the data bus. (If DB0–DB7 e high, the security
byte will contain FFH.)
f. Read two consecutive known bytes from the
EPROM array and verify that the wrong data are
retrieved in at least one verification. If the
EPROM can still be read, the security bit may
have not been fully programmed though the security byte in the signature mode has.
Verification
Since the security bit address overlaps the address
of the security byte of the signature mode, it can be
used to check indirectly whether the security bit has
been programmed or not. Therefore, the security bit
verification is a mere read operation of the security
byte of the signature row (0FFH e security bit programmed; 00H e security bit unprogrammed). Note
that during the security bit programming, the reading
of the security byte does not necessarily indicate
that the security bit has been successfully programmed. Thus, it is recommended that two consecutive known bytes in the EPROM array be read and
the wrong data should be read at least once, because it is highly improbable that random data coincides with the correct ones twice.
SIGNATURE MODE
The UPI-C42 has an additional 64 bytes of EPROM
available for Intel and user signatures and miscellaneous purposes. The 64 bytes are partitioned as follows:
A. Test code/checksumÐThis can accommodate
up to 25 bytes of code for testing the internal
nodes that are not testable by executing from the
external memory. The test code/checksum is
present on ROMs, and OTPs.
B. Intel signatureÐThis allows the programmer to
read from the UPI-41AH/42AH/C42 the manufacturer of the device and the exact product
name. It facilitates automatic device identification
and will be present in the ROM and OTP versions. Location 10H contains the manufacturer
code. For Intel, it is 89H. Location 11H contains
the device code.
The code is 43H and 42H for the 8042AH/80C42
and OTP 8742AH/87C42, respectively. The
code is 44H for any device with the security bit
set by Intel.
C. User signatureÐThe user signature memory is
implemented in the EPROM and consists of 2
bytes for the customer to program his own signature code (for identification purposes and quick
sorting of previously programmed materials).
D. Test signatureÐThis memory is used to store
testing information such as: test data, bin number, etc. (for use in quality and manufacturing
control).
E. Security byteÐThis byte is used to check
whether the security bit has been programmed
(see the security bit section).
F. UPI-C42 Intel SignatureÐApplies only to
CHMOS device. Location 20H contains the manufacturer code and location 21H contains the device code. The Intel UPI-C42 manufacturer’s
code is 99H. The device ID’s are 82H for the
OTP version and 83H for the ROM version. The
device ID’s are the same for the UPI-L42.
The signature mode can be accessed by setting
P10 e 0, P11 – P17 e 1, and then following the programming and/or verification procedures. The location of the various address partitions are as shown in
Table 3.
SYNC MODE
The Sync Mode is provided to ease the design of
multiple controller circuits by allowing the designer
to force the device into known phase and state time.
The Sync Mode may also be utilized by automatic
test equipment (ATE) for quick, easy, and efficient
synchronizing between the tester and the DUT (device under test).
Sync Mode is enabled when SS pin is raised to high
voltage level of a 12 volts. To begin synchronization, T0 is raised to 5 volts at least four clock cycles
after SS. T0 must be high for at least four X2 clock
cycles to fully reset the prescaler and time state
generators. T0 may then be brought down during
low state of X2. Two clock cycles later, with the rising edge of X2, the device enters into Time State 1,
Phase 1. SS is then brought down to 5 volts 4 clocks
later after T0. RESET is allowed to go high 5 tCY (75
clocks) later for normal execution of code.
11
UPI-C42/UPI-L42
Table 3. Signature Mode Table
Address
Device
Type
No. of
Bytes
Test Code/Checksum
0
16H
0FH
1EH
ROM/OTP
25
Intel Signature
10H
11H
ROM/OTP
2
User Signature
12H
13H
OTP
2
Test Signature
14H
Security Byte
1FH
or
15H
ROM/OTP
2
3FH
ROM/OTP
2
UPI-C42 Intel Signature
20H
21H
ROM/OTP
2
User Defined UPI-C42 OTP EPROM Space
22H
3EH
ROM/OTP
30
ACCESS CODE
The following table summarizes the access codes required to invoke the Sync Mode, Signature Mode,
and the Security Bit, respectively. Also, the programming and verification modes are included for
comparison.
Control Signals
Access Code
Data Bus
Modes
Port 2
T0 RST SS EA PROG VDD VCC 0
Programming
Mode
Verification
Mode
Sync Mode
Signature Prog
Mode
Verify
Security
Bit/Byte
Prog
Verify
1
2
3
4
5
6
7
0
0
1 HV
VDDH VCC
Address
Addr
1
1 HV STB VDDH VCC
Data In
Addr
0
0
1 HV
1
VCC VCC
Address
Addr
1
1
1 HV
1
VCC VCC
Data Out
Addr
STB
High
0
X
VCC VCC X
HV 0
1
VDDH VCC
X
X
X
X
X
X
Port 1
0 1 2 3 0 1 2 3 4 5 6 7
0
a0 a1 X X X X X X
a0 a1 X X X X X X
X X X X
X X X X X X X X
Addr. (see Sig Mode Table)
0 0 0
0 1 1 1 1 X X 1
Data In
0 0 0
0
0
1 HV
0
1
1 HV STB VDDH VCC
0
0
1 HV
1
VCC VCC
Addr. (see Sig Mode Table)
0 0 0
1
1
1 HV
1
VCC VCC
Data Out
0 0 0
1
0
0
1 HV
VDDH VCC
Address
0 0 0
0
1
1 HV STB VDDH VCC
Data In
0 0 0
0
0
1 HV
1
VCC VCC
Address
0 0 0
1
1
1 HV
1
VCC VCC
Data Out
0 0 0
NOTE:
1. a0 e 0 or 1; a1 e 0 or 1. a0 must e a1.
12
1
UPI-C42/UPI-L42
SYNC MODE TIMING DIAGRAMS
290414 – 15
Minimum Specifications
SYNC Operation Time, tSYNC e 3.5 XTAL 2 Clock cycles. Reset Time, tRS e 4 tCY.
NOTE:
The rising and falling edges of T0 should occur during low state of XTAL 2 clock.
APPLICATIONS
290414 – 12
Figure 7. UPI-C42 Keyboard Controller
290414 – 9
Figure 8. 8088-UPI-C42 Interface
13
UPI-C42/UPI-L42
APPLICATIONS (Continued)
290414 – 10
Figure 9. 8048H-UPI-C42 Interface
290414 – 11
Figure 10. UPI-C42-8243 Keyboard Scanner
290414 – 13
Figure 11. UPI-C42 80-Column Matrix Printer Interface
14
UPI-C42/UPI-L42
ABSOLUTE MAXIMUM RATINGS*
NOTICE: This is a production data sheet. The specifications are subject to change without notice.
Ambient Temperature Under Bias ÀÀÀÀ0§ C to a 70§ C
Storage Temperature ÀÀÀÀÀÀÀÀÀÀ b 65§ C to a 150§ C
Voltage on Any Pin with
Respect to GroundÀÀÀÀÀÀÀÀÀÀÀÀÀÀ b 0.5V to a 7V
Power Dissipation ÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀ1.5 W
DC CHARACTERISTICS
Symbol
VIL
*WARNING: Stressing the device beyond the ‘‘Absolute
Maximum Ratings’’ may cause permanent damage.
These are stress ratings only. Operation beyond the
‘‘Operating Conditions’’ is not recommended and extended exposure beyond the ‘‘Operating Conditions’’
may affect device reliability.
TA e 0§ C to a 70§ C, VCC e VDD e a 5V g 10%; a 3.3V g 10% UPI-L42
Parameter
Input Low Voltage
UPI-C42
UPI-L42
Units
Min
Max
Min
Max
b 0.5
0.8
b 0.3
a 0.8
V
V
Notes
All Pins
VIH
Input High Voltage
(Except XTAL2, RESET)
2.0
VCC
2.0
VCC a 0.3
VIH1
Input High Voltage
(XTAL2, RESET)
3.5
VCC
2.0
VCC a 0.3
V
VOL
Output Low Voltage (D0 –D7)
0.45
0.45
V
IOL e 2.0 mA UPI-C42
IOL e 1.3 mA UPI-L42
VOL1
Output Low Voltage
(P10P17, P20P27, Sync)
0.45
0.45
V
IOL e 1.6 mA UPI-C42
IOL e 1 mA UPI-L42
VOL2
Output Low Voltage (PROG)
0.45
0.45
V
IOL e 1.0 mA UPI-C42
IOL e 0.7 mA UPI-L42
VOH
Output High Voltage (D0 –D7)
2.4
2.4
V
IOH e b 400 mA UPI-C42
IOH e b 260 mA UPI-L42
VOH1
Output High Voltage
(All Other Outputs)
2.4
2.4
IIL
Input Leakage Current
(T0, T1, RD, WR, CS, A0, EA)
g 10
g 10
mA
VSS s VIN s VCC
IOFL
Output Leakage Current
(D0 –D7, High Z State)
g 10
g 10
mA
VSS a 0.45 s VOUT s VCC
ILI
Low Input Load Current
(P10P17, P20P27)
b 50 b 250 b 35
b 175
mA
Port Pins
Min VIN e 2.4V
Max VIN e 0.45V
ILI1
Low Input Load Current
(RESET, SS)
b 40
b 40
mA
VIN s VIL
IHI
Port Sink Current
(P10P17, P20P27)
5.0
mA
VCC e 3.0V
VIH e 5.0V
IDD
VDD Supply Current
2.5
mA
4
IOH e b 50 mA UPI-C42
IOH e b 25 mA UPI-L42
15
UPI-C42/UPI-L42
DC CHARACTERISTICS
TA e 0§ C to a 70§ C, VCC e VDD e a 5V g 10%; a 3.3V g 10% UPI-L42 (Continued)
Symbol
ICC a IDD
UPI-C42
Parameter
Min
Max
UPI-L42
Min
Max
Units
Notes
Typical 14 mA UPI-C42,
9 mA UPI-L42
Osc. Off(1, 4)
Total Supply Current:
Active Mode @ 12.5 MHz
30
20
mA
Suspend Mode
40
26
mA
IDD Standby
Power Down
Supply Current
5
3.5
mA
NMOS Compatible
Power Down Mode
IIH
Input Leakage Current
(P10 –P17, P20 –P27)
100
100
mA
VIN e VCC
CIN
Input Capacitance
10
10
pF
TA e 25§ C (1)
CIO
I/O Capacitance
20
20
pF
TA e 25§ C (1)
NOTE:
1. Sampled, not 100% tested.
DC CHARACTERISTICSÐPROGRAMMING (UPI-C42 AND UPI-L42)
TA e 25§ C g 5§ C, VCC e 6.25V g 0.25V, VDD e 12.75V g 0.25V
Symbol
Parameter
Min
Max
Units
VDDH
VDD Program Voltage High Level
12.5
13
V(1)
VDDL
VDD Voltage Low Level
4.75
5.25
V
VPH
PROG Program Voltage High Level
2.0
5.5
V
VPL
PROG Voltage Low Level
b 0.5
0.8
V
VEAH
Input High Voltage for EA
12.0
13.0
V(2)
VEAL
EA Voltage Low Level
b 0.5
5.25
V
IDD
VDD High Voltage Supply Current
50.0
mA
IEA
EA High Voltage Supply Current
1.0
mA(4)
NOTES:
1. Voltages over 13V applied to pin VDD will permanently damage the device.
2. VEAH must be applied to EA before VDDH and removed after VDDL.
3. VCC must be applied simultaneously or before VDD and must be removed simultaneously or after VDD.
4. Sampled, not 100% tested.
16
UPI-C42/UPI-L42
AC CHARACTERISTICS
TA e 0§ C to a 70§ C, VSS e 0V, VCC e VDD e a 5V g 10%; a 3.3V g 10% for the UPI-L42
NOTE:
All AC Characteristics apply to both the UPI-C42 and UPI-L42
DBB READ
Symbol
Parameter
Min
v
u
tAR
CS, A0 Setup to RD
tRA
CS, A0 Hold After RD
tRR
RD Pulse Width
tAD
CS, A0 to Data Out Delay
tRD
RD
tDF
RD
Max
0
ns
0
ns
160
v to Data Out Delay
u to Data Float Delay
Units
ns
130
0
ns
130
ns
85
ns
Max
Units
DBB WRITE
Symbol
Parameter
Min
0
tWA
v
CS, A0 Hold After WRu
tWW
WR Pulse Width
tDW
Data Setup to WR
tWD
Data Hold After WR
tAW
CS, A0 Setup to WR
u
u
ns
0
ns
160
ns
130
ns
0
ns
17
UPI-C42/UPI-L42
AC CHARACTERISTICS
TA e 0§ C to a 70§ C, VSS e 0V, VCC e VDD e a 5V g 10%; a 3.3V g 10% for the UPI-L42 (Continued)
CLOCK
Min
Max
Units
tCY UPI-C42/UPI-L42
Symbol
Cycle Time
Parameter
1.2
9.20
ms(1)
tCYC UPI-C42/UPI-L42
Clock Period
80
613
ns
tPWH
Clock High Time
30
tPWL
Clock Low Time
30
tR
Clock Rise Time
10
ns
tF
Clock Fall Time
10
ns
ns
ns
NOTE:
1. tCY e 15/f(XTAL)
AC CHARACTERISTICS
DMA
Symbol
Parameter
Min
tACC
DACK to WR or RD
tCAC
RD or WR to DACK
0
tACD
DACK to Data Valid
0
tCRQ
RD or WR to DRQ Cleared
Max
Units
0
ns
ns
130
ns
110
ns(1)
NOTE:
1. CL e 150 pF.
AC CHARACTERISTICS
PORT 2
Parameter
f(tCY)(3)
Min
tCP
Port Control Setup Before Falling Edge of PROG
1/15 tCY b 28
55
ns(1)
tPC
Port Control Hold After Falling Edge of PROG
1/10 tCY
125
ns(2)
tPR
PROG to Time P2 Input Must Be Valid
tPF
Input Data Hold Time
tDP
Output Data Setup Time
2/10 tCY
250
ns(1)
tPD
Output Data Hold Time
1/10 tCY b 80
45
ns(2)
tPP
PROG Pulse Width
6/10 tCY
750
ns
Symbol
NOTES:
1. CL e 80 pF.
2. CL e 20 pF.
3. tCY e 1.25 ms.
18
8/15 tCY b 16
0
Max
Units
650
ns(1)
150
ns(2)
UPI-C42/UPI-L42
AC CHARACTERISTICSÐPROGRAMMING (UPI-C42 AND UPI-L42)
TA e 25§ C g 5§ C, VCC e 6.25V g 0.25V, VDDL e a 5V g 0.25V, VDDH e 12.75V g 0.25V
(87C42/87L42 ONLY)
Symbol
Parameter
Min
tWD
u
u
Data in Setup Time to PROGv
Data in Hold Time after PROGu
tPW
Initial Program Pulse Width
tTW
Test 0 Setup Time for Program Mode
4tCY
tWT
Test 0 Hold Time after Program Mode
4tCY
tDO
Test 0 to Data Out Delay
tWW
RESET Pulse Width to Latch Address
tr, tf
PROG Rise and Fall Times
tCY
CPU Operation Cycle Time
tRE
RESET Setup Time before EA
tOPW
Overprogram Pulse Width
2.85
tDE
EA High to VDD High
1tCY
tAW
Address Setup Time to RESET
4tCY
tWA
Address Hold Time after RESET
4tCY
tDW
Max
Units
105
ms
4tCY
4tCY
95
4tCY
u
4tCY
0.5
100
ms
2.5
3.75
ms
78.75
ms(1)
4tCY
NOTES:
1. This variation is a function of the iteration counter value, X.
2. If TEST 0 is high, tDO can be triggered by RESETu.
AC TESTING INPUT/OUTPUT WAVEFORM
AC TESTING LOAD CIRCUIT
INPUT/OUTPUT
290414 – 16
290414 – 17
19
UPI-C42/UPI-L42
DRIVING FROM AN EXTERNAL SOURCE
290414 – 18
LC OSCILLATOR MODE
L
C
NOMINAL
45 H 20 pF 5.2 MHz
120 H 20 pF 3.2 MHz
290414 – 19
Rise and Fall Times Should Not
Exceed 10 ns. Resistors to VCC
are Needed to Ensure VIH e 3.5V
if TTL Circuitry is Used.
NOTE:
See XTAL1 Configuration Table.
CRYSTAL OSCILLATOR MODE
fe
1
2q0LCÊ
CÊ e
C a 3Cpp
2
Cpp j 5– 10 pF
Pin-to-Pin Capacitance
290414 – 20
Each C Should be Approximately 20 pF, including Stray Capacitance.
C1
C2
C3
290414 – 21
5 pF (STRAY 5 pF)
(CRYSTAL a STRAY) 8 pF
20 – 30 pF INCLUDING STRAY
Crystal Series Resistance Should
be Less Than 30X at 12.5 MHz.
XTAL1 Configuration Table
XTAL1 Connection
1) to Ground
Not recommended for CHMOS
designs. Causes approximately
16 mA of additional current flow
through the XTAL1 pin on UPIC42 and approximately 11 mA of
additional current through XTAL1
on the UPI-L42.
20
2) 10 KX Resistor
to Ground
Recommended configuration for
designs which will use both
NMOS and CHMOS parts. This
configuration limits the additional
current through the XTAL1 pin to
approximately 1 mA, while
maintaining compatibility with the
NMOS device.
3) Not Connected
Low power configuration
recommended for CHMOS only
designs to provide lowest
possible power consumption.
This configuration will not work
with the NMOS device.
UPI-C42/UPI-L42
WAVEFORMS
READ OPERATIONÐDATA BUS BUFFER REGISTER
290414 – 22
WRITE OPERATIONÐDATA BUS BUFFER REGISTER
290414 – 23
CLOCK TIMING
290414 – 24
21
UPI-C42/UPI-L42
WAVEFORMS (Continued)
COMBINATION PROGRAM/VERIFY MODE
290414 – 25
NOTES:
1. A0 must be held low (0V) during program/verify modes.
2. For VIH, VIH1, VIL, VIL1, VDDH, and VDDL, please consult the D.C. Characteristics Table.
3. When programming the 87C42, a 0.1 mF capacitor is required across VDD and ground to suppress spurious voltage
transients which can damage the device.
VERIFY MODE
290414 – 26
NOTES:
1. PROG must float if EA is low.
2. PROG must float or e 5V when EA is high.
3. P10 – P17 e 5V or must float.
4. P24 – P27 e 5V or must float.
5. A0 must be held low during programming/verify modes.
22
UPI-C42/UPI-L42
WAVEFORMS (Continued)
DMA
290414 – 27
PORT 2
290414 – 28
PORT TIMING DURING EXTERNAL ACCESS (EA)
290414 – 29
On the Rising Edge of SYNC and EA is Enabled, Port Data is Valid and can be Strobed. On the Trailing Edge of Sync
the Program Counter Contents are Available.
23
UPI-C42/UPI-L42
Table 4. UPI Instruction Set
Mnemonic
Description
ACCUMULATOR
ADD A, Rr
Add register to A
Add data memory
ADD A, @ Rr
to A
Add immediate to A
ADD A, Ýdata
ADDC A, Rr
Add register to A
with carry
Add data memory
ADDC A, @ Rr
to A with carry
ADDC A, Ýdata Add immediate
to A with carry
ANL A, Rr
AND register to A
AND data memory
ANL, A @ Rr
to A
ANL A, Ýdata
AND immediate to A
ORL A, Rr
OR register to A
OR data memory
ORL, A, @ Rr
to A
OR immediate to A
ORL A, Ýdata
XRL A, Rr
Exclusive OR register to A
Exclusive OR data
XRL A, @ Rr
memory to A
Exclusive OR immeXRL A, Ýdata
diate to A
INC A
Increment A
DEC A
Decrement A
CLR A
Clear A
CPL A
Complement A
DA A
Decimal Adjust A
SWAP A
Swap nibbles of A
RL A
Rotate A left
RLC A
Rotate A left through
carry
RR A
Rotate A right
RRC A
Rotate A right
through carry
INPUT/OUTPUT
IN A, Pp
Input port to A
OUTL Pp, A
Output A to port
ANL Pp, Ýdata AND immediate to
port
ORL Pp, Ýdata OR immediate to
port
IN A, DBB
Input DBB to A,
clear IBF
OUT DBB, A
Output A to DBB,
set OBF
MOV STS, A
A4 – A7 to Bits 4–7 of
Status
MOVD A, Pp
Input Expander
port to A
MOVD Pp, A
Output A to
Expander port
ANLD Pp, A
AND A to Expander
port
ORLD Pp, A
OR A to Expander
port
24
Bytes
Cycles
Mnemonic
1
1
1
1
DATA MOVES
MOV A, Rr
MOV A, @ Rr
2
1
2
1
1
1
2
2
1
1
1
1
2
1
1
2
1
1
2
1
2
1
1
1
2
2
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
2
2
2
2
EN I
2
2
EN FLAGS
1
1
*SEL PMB0
1
1
*SEL PMB1
1
1
SEL RB0
1
2
SEL RB1
1
2
1
2
1
2
MOV A, Ýdata
MOV Rr, A
MOV @ Rr, A
MOV Rr, Ýdata
MOV @ Rr,
Ýdata
MOV A, PSW
MOV PSW, A
XCH A, Rr
XCH A,
@ Rr
XCHD A,
@ Rr
MOVP A,
@A
MOVP3, A,
@A
Description
Bytes
Cycles
Move register to A
Move data memory
to A
Move immediate to A
Move A to register
Move A to data
memory
Move immediate to
register
Move immediate to
data memory
Move PSW to A
Move A to PSW
Exchange A and
register
Exchange A and
data memory
Exchange digit of A
and register
Move to A from
current page
Move to A from
page 3
1
1
1
1
2
1
1
2
1
1
2
2
2
2
1
1
1
1
1
1
1
1
1
1
1
2
1
2
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
TIMER/COUNTER
MOV A, T
Read Timer/Counter
MOV T, A
Load Timer/Counter
STRT T
Start Timer
STRT CNT
Start Counter
STOP TCNT
Stop Timer/Counter
EN TCNTI
Enable Timer/
Counter Interrupt
DIS TCNTI
Disable Timer/
Counter Interrupt
CONTROL
*EN A20
EN DMA
DIS I
Enable A20 Logic
Enable DMA Handshake Lines
Enable IBF Interrupt
Diable IBF Interrupt
Enable Master
Interrupts
Select Program
memory bank 0
Select Program
memory bank 1
Select register
bank 0
Select register
bank 1
* UPI-C42/UPI-L42 Only.
UPI-C42/UPI-L42
Table 4. UPI Instruction Set (Continued)
Mnemonic
Description
CONTROL (Continued)
*SUSPEND Invoke Suspend Powerdown mode
NOP
No Operation
REGISTERS
INC Rr
Increment register
INC @ Rr
Increment data
memory
DEC Rr
Decrement register
SUBROUTINE
CALL addr
Jump to subroutine
RET
Return
RETR
Return and restore
status
FLAGS
CLR C
CPL C
CLR F0
CPL F0
CLR F1
CPL F1
Clear Carry
Complement Carry
Clear Flag 0
Complement Flag 0
Clear F1 Flag
Complement F1 Flag
Bytes
Cycles
1
2
1
1
1
1
1
1
1
1
2
1
1
2
2
2
1
1
1
1
1
1
1
1
1
1
1
1
Mnemonic
BRANCH
JMP addr
JMPP @ A
DJNZ Rr, addr
JC addr
JNC addr
JZ addr
JNZ addr
JT0 addr
JNT0 addr
JT1 addr
JNT1 addr
JF0 addr
JF1 addr
JTF addr
JNIBF addr
JOBF addr
JBb addr
Description
Bytes
Cycles
Jump unconditional
Jump indirect
Decrement register
and jump
Jump on Carry e 1
Jump on Carry e 0
Jump on A Zero
Jump on A not Zero
Jump on T0 e 1
Jump on T0 e 0
Jump on T1 e 1
Jump on T1 e 0
Jump on F0 Flag e 1
Jump on F1 Flag e 1
Jump on Timer Flag
e 1, Clear Flag
Jump on IBF Flag
e0
Jump on OBF Flag
e1
Jump on Accumulafor Bit
2
1
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
*UPI-C42/UPI-L42 Only.
REVISION SUMMARY
The following has been changed since Revision
-003:
1. Delete all references to standby power down
mode.
The following has been changed since Revision
-002:
1. Added information on keyboard controller product family.
2. Added IHI specification for the UPI-L42.
The following has been changed since Revision
-001:
1. Added UPI-L42 references and specification.
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