SILAN SC84510FP

Silan
Semiconductors SC84510
PS/2 SCROLLING MOUSE
CONTROLIER
DESCRIPTION
The SC84510 Scrolling Mouse Controller is specially designed to
control PS/2 mouse device. This single chip can interface three keyswitches four photo-couples plus x-axis direct to 8042 controller.
SC84510 can receive command and echo status or data format
which are compatible with IBM PS/2 mode mouse.
Key debouncing circuit is provided to prevent false entry and
improve the accuracy.
In the traditional mouse, a great number of noises are generated
when the grid is partially closed or opened. These noises are usually
DIP-16
mistaken for movement signals by traditional mouse controller and
the cursor of the display screen is thus moved frequently up and
down or back and forth. This will consume a great amount of energy.
The SC84510 mouse controller provides noise immunity circuits to
eliminate these noises in order to reduce energy consumption.
FEATURES
* Low power dissipation.
* Using 50k ±5% resistor for RC oscillation.
* Six types Z direction input:
* Compatible with legacy PS/2 mouse.
* Compatible with Microsoft scrolling mouse.
1. Photo couples input. (Z/1)
* Built-in noise immunity circuit.
2. Key-switches input.
* Built-in current comparator for photo-couples input.
3. Voltage-sensing input.
* Built-in three steps dynamic input impedance.
4. Mechanical input. (Z/1)
* Three key-switches and four photo-couples inputs.
5. Photo couples input. (Z/4)
* Both key-press and key-release debounce interval 12 ms.
6. Mechanical input. (Z/2)
* The sampling rate of motion detector is about 65KHz.
ORDERING INFORMATION
SC84510AP
DIP-16 Package, Photo couples input. (Z/1)
SC84510BP
DIP-16 Package, Key-switches input.
SC84510CP
DIP-16 Package, Voltage-sensing input.
SC84510DP
DIP-16 Package, Mechanical input. (Z/1)
SC84510EP
DIP-16 Package, Photo couples input. (Z/4)
SC84510FP
DIP-16 Package, Mechanical input. (Z/2)
HANGZHOU SILAN MICROELECTRONICS JOINT-STOCK CO.,LTD
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Silan
Semiconductors SC84510
PIN CONFIGURATIONS
1
16 OSCR
OSC OUT
2
15 Y2
Z1
3
Z2
4
CLK
5
DATA
6
OPT
7
10 M
VSS
8
9
SC84510A/B/C/E/F
VDD
14 Y1
13 X2
12 X1
11 L
R
BLOCK DIAGRAM
DATA
CLK
6
5
THREE TYPES SELECTOR
Z1
3
Z2
4
COMPARATOR
VOLTAGE
SENSOR
KEY-SWITCH
DETECTOR
Z-AXIS COUNTER
X2
13
Y1
14
Y2
15
L
11
M
10
R
9
OSCR
16
OSC.OUT
2
COUNTER
MULTIPLEXER
DEBOUNCE
12
DETECTOR
7
X1
COMPARATOR
OPT
COMMAND
STATUS
DATA
I/O
TIMING
CONTROLLER
SYSTEM CLOCK GENERATOR
RC & CRYSTAL OSCILLATION
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Semiconductors SC84510
ABSOLUTE MAXIMUM RATINGS (Tamb=25°C, unless otherwise specified)
Characteristic
Symbol
Value
Unit
Temperature Under Bias
TOPR
0 ~ 70
°C
Storage Temperature range
TSTR
-65 ~ +150
°C
Input Voltage
VIN
-0.3 ~ +6.0
V
Output Voltage
VO
-0.3 ~ +6.0
V
DC ELECTRICAL CHARACTERISTICS (Tamb=25~70°C)
Parameter
Symbol
Min
Typ
Max
Unit
VDD
4.5
5
5.5
V
Iop
--
--
1.2
mA
Vt+
0.6VDD
--
0.8 VDD
V
Vt-
0.2 VDD
--
0.4 VDD
V
(Vin=0V)
Idc
0.56
--
1.86
mA
(Iprl=-4mA)
Vprl
--
--
0.4
V
Ipl
60
--
--
µA
Iph
--
--
110
µA
Vpi
0.8
--
1.2
V
Vpi
1.5
--
2.8
V
L, M, R, OPT, Z1, Z2 (Key Mode) Input Low Voltage
Vail
--
--
0.3 VDD
V
L, M, R, OPT, Z1, Z2 (Key Mode) Input High Voltage
Vaih
0.7 VDD
--
--
V
Rmi
92
--
310
kΩ
Operating Voltage
Operating Current
(No Load)
CLK, DATA
Positive-going Threshold Voltage
CLK, DATA
Negative-going Threshold Voltage
DATA, CLK Input Current (pull up resistor)
DATA, CLK Low Output Voltage
X1, X2, Y1, Y2, Z1, Z2 (Photo Mode)
Low Input Reference Current
X1, X2, Y1, Y2, Z1, Z2 (Photo Mode)
High Input Reference Current
X1, X2, Y1, Y2, Z1, Z2 (Photo Mode)
Input Current
(Input Impedance) (80µA)
X1, X2, Y1, Y2, Z1, Z2 (Photo Mode)
Input Current
(Input Impedance) (500µA)
L, M, R, Z1, Z2 (Key & Voltage Mode)
Input Resistor
(Vin=VDD)
OPT Input Resistor
(Vin=VDD)
Rxi
133
--
400
kΩ
OPT High Output Current
(Vin=VDD)
Vopt
4.5
--
--
V
Iil
0
--
-1.0
µA
3.2
--
--
4.5
--
--
5.5
--
--
L, M, R, X1, X2, Y2, Y2, Z1, Z2
Input Leakage Current
(Vin=0V)
VDD=4.5V
OPT High Output Current (Iopt=10mA)
VDD=5V
VDD=5.5V
Idc
V
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Semiconductors Note:
SC84510
1. All voltage in above table are compared with VSS.
2. All parameters in above table are tested under VDD=5V.
3. CLK & DATA output gates are open drains that connect to pull up resistors.
X1, X2, Y1, Y2 input impedance
UNIT:K¡
MAX.
16.0
15.0
14.0
TYP.
13.0
12.0
MIN.
11.0
10.0
9.0
8.0
7.0
6.0
5.0
4.0
3.0
2.0
1.0
0
1.0
10.0M
2.0
3.0
4.0
5.0
VOLTAGE (LIN)
AC ELECTRICAL CHARACTERISTICS (Tamb=25~70°C)
Symbol
Min
Typ
Oscillating Frequency
Parameter
Fosc
34.3-10%
34.3
Key Debounce
Tkd
--
12
Max
Unit
34.3+10% kHz
--
ms
Rising Edge Crossed Width Fosc=35KHz
Tr
14.3
--
--
µs
Falling Edge Crossed Width
Tf
14.3
--
--
µs
Tmca
--
42.9
--
µs
Mouse CLK Inactive Time
Tmci
--
42.9
--
µs
Mouse Sample DATA from CLK rising Edge
Tmdc
--
14.3
--
µs
System CLK Active Time
Tsca
--
42.9
--
µs
Mouse CLK Active Time
System CLK Inactive Time
Tsci
--
42.9
--
µs
Time from DATA Transition to Falling Edge of CLK
Tsdc
--
14.3
--
µs
Time from rising Edge of CLK to DATA Transition
Tscd
--
28.6
--
µs
Tpi
0
--
50
µs
Time to mouse Inhibit after the 11th CLK to ensure mouse does
not start another Transmission
The AC timings are measured under using 35KHz system clock signal.
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Semiconductors SC84510
PIN DESCRIPTION
Pin Name
I/O
Description
INPUT: 200kΩ pull low to VSS.
When OPT is connected to VDD, SC84510 will enter test mode. In test mode, L will
be the output of X1, while M will be the output of X2. Toggling R key can change
OPT
I/O
these output to be Y1, Y2 or Z1, Z2 respectively.
OUTPUT: 2kHz Z-axis LED-driving source.
“1” = VDD, “0” = floating
High duty is about 60µs.
OSC OUT
O
OSCR
I
CLK
I/O
Connect to 8042 auxiliary port CLK line.
DATA
I/O
Connect to 8042 auxiliary port DATA line.
RC mode oscillation with 50kΩ resistor.
R
I
M
Three key-switches inputs.
200kΩ resistor pull low.
L
X1
X2
I
Three step dynamic input impedance.
Use current comparator to measure photo-couples “ON”, or “OFF”.
Y1
Y2
Z-axis input.
Z1
Photo mode: Three steps dynamic input impedance. Current comparator input.
I
Z2
Key mode: 200kΩ resistor pull low. 7 levels increased by “M” key.
Voltage mode: 200kΩ resistor pull low. 7 levels voltage comparator.
Mechanical mode: 13.2kΩ resistor pull low.
VSS
Negative power.
VDD
Power line.
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Semiconductors SC84510
FUNCTION DESCRIPTIONS
1. LEGACY PS/2 MOUSE OPERATING
(A) Operating mode
There are four operating modes in PS/2 mouse:
(a) Reset Mode:
In this mode a self-test is initiated during power-on or by a Reset command. After reset signal, PS/2 mouse
will send:
a Completion code AA & ID code 00.
b Set default:
* sampling rate: 100 reports/s
* non-autospeed
* stream mode
* 2 dot/count
* disable
(b) Stream Mode:
The maximum rate of transfer is the programmed sample rate.
Data report is transmitted if
a switch is pressed
b movement has been detect
(c) Remote Mode:
Data is transmitted only in response to a Read Data command.
(d) Wrap Mode:
Any byte of data sent by the system, except hex EC (Reset wrap mode) or hex FF (Reset), is returned by
SC84510.
(B) PS/2 Mouse Data Report:
(a) In stream mode: A data report is sent at the end of a sample interval.
(b) In remote mode: A data report is sent in response to Read Data command.
(c) Data report format:
Byte
Bit
Description
1
0
Left button status; 1 = pressed
1
Right button status; 1 = pressed
2
Middle button status; 1 = pressed
3
Reserve
4
X data sign; 1 = negative
5
Y data sign; 1 = negative
6
X data overflow; 1 = overflow
7
Y data overflow; 1 = overflow
2
0~7
X data (D0~D7)
3
0~7
Y data (D0~D7)
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Semiconductors SC84510
(C) PS/2 mouse Data Transmission:
(a) SC84510 generates the clocking signal when sending data to and receiving data from the system.
(b) The system requests SC84510 receive system data output by forcing the DATA line to an inactive level and
allowing CLK line to go to an active level.
(c) Data transmission frame:
Bit
Function
1
Start bit (always 0)
2~9
Data bits (D0~D7)
10
Parity bit (odd parity)
11
Stop bit (always 1)
(d) Data Output (data from SC84510 to system):
If CLK is low (inhibit status), data is no transmission.
If CLK is high and DATA is low (request-to-send), data is updated. Data is received from the system and
no transmission are started by SC84510 until CLK and DATA both high. If CLK and DATA are both high, the
transmission is ready. DATA is valid prior to the falling edge of CLK and beyond the rising edge of CLK.
During transmission, SC84510 check for line contention by checking for an inactive level on CLK at intervals
not to exceed 100µ sec. Contention occurs when the system lowers CLK to inhibit SC84510 output after
SC84510 has started a transmission. If this occurs before the rising edge of the tenth clock, SC84510 internal
store its data in its buffer and returns DATA and CLK to an active level. If the contention does not occur by the
tenth clock, thetransmission is complete.
Following a transmission, the system inhibits SC84510 by holding CLK low until it can service the input or
until the system receives a request to send a response from SC84510.
(e) Data Input (from system to SC84510):
System first check if SC84510 is transmitting data. If SC84510 is transmitting, the system can override
the output forcing CLK to an inactive level prior to the tenth clock. If SC84510 transmission is beyond the
tenth clock, the system receives the data. If SC84510 is not transmitting or if the system choose to override
the output, the system force CLK to an inactive level for a period of not less than 100µ sec while preparing for
output. When the system is ready to output start bit (0), it allows CLK go to active level. If request-to-send is
detected, SC84510 clocks 11 bits. Following the tenth clock SC84510 checks for an active level on the DATA
line, and if found, force DATA low, and clock once more. If occurs framing error, SC84510 continue to clock
until DATA is high, then clocks the line control bit and request a Resend. When the system sends out a
command or data transmission that requires a response, the system waits for SC84510 to response before
sending its next output.
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Semiconductors SC84510
(D) PS/2 Mouse Error Handling:
(a) A Resend command (FE) following receipt of an invalid input or any input with incorrect parity.
(b) If two invalid input are received in succession, an error code of hex FC send to the system.
(c) The counter accumulators are cleared after receiving any command except “Resend”.
(d) SC84510 receives a Resend command (FE), it transmit its last packet of data.
(e) In the stream mode “Resend” is received by SC84510 following a 3-byte data packet transmission to the
system. SC84510 resend the 3-byte data packet prior to clearing the counter.
(f) A response is sent within 25 ms if
a The system requires a response
b An error is detected in the transmission
(g) When a command requiring a response is issued by the system, another command should not be issue until
either the response is received or 25ms has passed.
(E) PS/2 Mouse Commands Description:
There are 16 valid commands that transmits between the system and SC84510. The “FA” code is always the
first response to any valid input received from the system other than a Set Wrap Mode or Resend command. The
following table list the commands:
The following describes valid commands:
Hex Code
Command
SC84510 echo code
FF
Reset
FA, AA, 00
FE
Resend
XX, (XX, XX)
F6
Set Default
FA
F5
Disable
FA
F4
Enable
FA
F3, XX
Set Sampling Rate
FA, FA
F2
Read Device Type
FA, 00
F0
Set Remote Mode
FA
EE
Set Wrap Mode
FA
EC
Reset Wrap Mode
FA
EB
Read Data
FA, XX, XX, XX
EA
Set Stream Mode
FA
E9
Status Request
FA, XX, XX, XX
E8, XX
Set Resolution
FA, FA
E7
Set Auto-speed
FA
E6
Reset Auto-speed
FA
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Semiconductors SC84510
The following describes valid command:
(a) Reset (FF)
SC84510 operation:
a Completion the reset.
b Transmitted FA, AA, 00 to the system.
c Set default:
sampling rate: 100 reports/s
non-auto-speed
stream mode
2 dots/count
disable
(b) Resend (FE)
a. Any time SC84510 receives an invalid command; it returns a Resend command to the system.
b. When SC84510 receives a Resend command, it retransmits its last packet of data. If the last packet was
a Resend command, it transmits the packet just prior to the Resend command.
c. In stream mode if a Resend command is received by SC84510 immediately following a 3-byte data
packet transmission to the system.
(c) Set Default (F6)
The command reinitializes all conditions to the power-on defaults.
(d) Disable (F5)
This command is used in the stream mode to stop transmissions from SC84510.
(e) Enable (F4)
Begins transmissions, if in stream mode.
(f) Set Sampling Rate (F3, XX)
In the stream mode, this command sets the sampling rate to the value indicated by byte hex XX, shown in
following:
Second byte XX
Sample Rate
0A
10/sec
14
20/sec
28
40/sec
3C
60/sec
50
80/sec
64
100/sec
C8
200/sec
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Semiconductors SC84510
(g) Read Device Type (F2)
SC84510 always echoes “ FA, 00 “ following this command.
(h) Set Remote Mode (F0)
Data values are reported only in response to a Read Data command.
(i) Set Wrap Mode (EE)
Wrap mode remains until Reset (FF) or Reset Wrap Mode (EC) is received.
(j) Reset Wrap Mode (EC)
SC84510 returns to the previous mode of operation after receiving this command.
(k) Read Data (EB)
This command is executed in either remote or stream mode. The data is transmitted even if there has
been no movement since the last report or the button status is unchanged. Following a Read Data
command, the registers are cleared after a data transmission.
(l) Set Stream Mode (EA)
This command sets SC84510 in stream mode.
(m) Status Request (E9)
When this command is issued by the system, SC84510 respond with a 3-byte status report as follows:
Byte
Bit
1
0
1 = Right button pressed
Description
1
1 = Middle button pressed
2
1 = Left button pressed
3
Reserved
4
0 = Normal speed, 1 = Auto-speed
5
0 = Disabled, 1 = Enabled
6
0 = stream mode, 1 = Remote mode
7
Reserved
2
0~7
Current resolution setting (D0~D7)
3
0~7
Current sampling rate (D0~D7)
(n) Set Resolution (E8, XX)
SC84510 provides four resolutions selected by the second byte of this command as follows:
Second Byte XX
Resolution
00
8 dots/count
01
4 dots/count
02
2 dots/count
03
1 dot/count
(o) Set Auto-speed (E7)
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Semiconductors SC84510
At the end of a sample interval in the stream mode, the current X and Y data values are converted new
values. The sign bits are not involved in this conversion. The conversion is only in stream mode. The
relationship between the input and output count follows:
Input
Output
0
0
1
1
2
1
3
3
4
6
5
9
N( ≥6)
2.0*N
(p) Reset Auto-speed (E6)
This command restores normal speed.
2. MICROSOFT PS/2 SCROLLING MOUSE MODE:
(A) Entering procedure: Except in WRAP mode, While SC84520 received the following consecutive command.
(a) F3 C8
---- set sampling rate 200/sec
(b) F3 64
---- set sampling rate 100/sec
(c) F3 50
---- set sampling rate 80/sec
(B) Operating:
(a) All of the command in legacy mode still is valid.
(b) The ID code of read device type command (F2) will changed from “00” to be “03”.
(c) Data report will be four bytes format:
Byte
Bit
Description
1
0
Left button status; 1 = pressed
1
Right button status; 1 = pressed
2
Middle button status; 1 = pressed
3
Reserve
4
X data sign; 1 = negative
5
Y data sign; 1 = negative
6
X data overflow; 1 = overflow
7
Y data overflow; 1 = overflow
2
0-7
X data (D0 – D7)
3
0-7
Y data (D0 – D7)
4
0-7
Z data (D0 – D7)
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Semiconductors SC84510
(C) Exiting Microsoft scrolling mode:
There are two ways to exit:
(a) Power off.
(b)Reset command (FF).
3. Z-AXIS INPUT FUNTION: The Z0 ~ Z7 limit value is ±7
(A) Photo couples input: Z-axis counter accumulates the Z1, Z2 phase changed by movement. This mode
includes noise immunity.
Z/1: 1 dot per count.
Z/4: 4 dots per count. Counted by Z1=1, Z2=1 phase, the wheel should stay at Z1=0, Z2=0 phase.
(B) Key-switches input: Pressing Z1, Z2 will start to fill the Z-axis counter with the value beginning at one.
Toggling “M” key can increase the value any time by one. The limit value is ±7.
The relationship between the value and the transmission rate as follow:
Value
Rate per second
1
2.7
2
6.4
3
9.2
4
12.8
5
15
6
18
7
20
(C) Voltage-sensing mode: There are 7 voltage levels in Z1, Z2 input. The transmission table is the same as keyswitch mode. The relationship between the value of Z-axis counter and the voltage as follows:
Value
Voltage
0
1V ↓
1
1.0V – 1.6V
2
1.6V – 2.2V
3
2.2V - 2.8V
4
2.8V – 3.4V
5
3.4V – 4.0V
6
4.0V – 4.6V
7
4.6V ↑
Under VDD = 5V condition
(D) Mechanical mode: The function is the same as photo couples input mode, except there is no noise immunity.
Z/1: 1 dot per count.
Z/2: 2 dots per count. Counted by Z2 changing phase.
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Semiconductors SC84510
TIMING DIAGRAM
(1) Photo-couples pulse width
X1(Y1)
X2(Y2)
Tr
Tf
(2) PS/2 Mouse
(A) Receiving Data
1st
CLK
Inhibit
CLK
2rd
CLK
9th
CLK
10th
CLK
11th
CLK
Tmca
Tmci
DATA
Tmdc
Start
Bit
Bit0-Bit7
Parity
Bit
Stop
Bit
Line
Control
Bit
(B) Sending Data
CLK
1st
CLK
Tscl
2nd
CLK
10th
CLK
11th
CLK
Tsca
Tpi
DATA
Tsdc
Tscd
Start
Bit
Bit0-Bit7
Parity
Bit
Stop
Bit
AC TIMING POINT
Output:
DATA
CLK PIN
VDD-2.6
VSS+0.4V
+1.6V
Input:
VSS
X1, X2, Y1, Y2 PIN
VDD-0.8V
VSS+0.8V
CLK, DATA PIN
VDD
L, M, R PIN
VSS
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Semiconductors SC84510
SC84510 I/O PIN EQUIVALENT CIRCUITS
CLK:
X1, X2, Y1, Y2:
X1,X2,Y1,Y2
PHASE DIGITAL SIGNAL
VCC
VCC
13.2kO
PS/2 MOUSE ENABLE
CLK
CLK INPUT SIGNAL
VCC
CLK INPUT SIGNAL
VCC
VPP/4
80­
13.2k
51k
R, M, L:
DATA:
VCC
(R,M,L)
(R, L, M)
INTERNAL SIGNAL
VCC
DATA
PS/2 MOUSE ENABLE
DATA INPUT SIGNAL
DATA INPUT SIGNAL
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APPLICATIONS CIRCUITS
1
2
1
VDD
Y2
15
3
4
5
CLK
Y1
14
5
6
DATA
X2
13
6
2
OSC OUT
X1
12
Z2
4
7
OPT
Z1
3
L
11
M
10
R
9
OSCR
51k
16
10­f
8
VSS
SC84510A/E
1
2
3
4
5
6
1
VDD
Y2
15
5
CLK
Y1
14
6
DATA
X2
13
7
OPT
X1
12
OSC OUT
Z2
4
Z1
3
51k
2
16
8
L
11
M
10
R
9
OSCR
VSS
10­f
SC84510B
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Semiconductors SC84510
APPLICATIONS CIRCUITS (continued)
1
2
3
4
5
6
1
VDD
Y2
15
5
CLK
Y1
14
6
DATA
X2
13
7
OPT
X1
12
2
Z2
OSC OUT
4
Z1
3
OSCR
L
11
M
10
R
9
51k
16
8
VSS
10­f
SC84510CP
1
2
3
4
5
6
1
VDD
Y2
15
5
CLK
Y1
14
6
DATA
X2
13
7
OPT
X1
12
2
Z2
4
A*
OSC OUT
Z1
3
B
L
11
M
10
R
9
OSCR
51k
16
8
VSS
10­f
COM
SC84510D/F
HANGZHOU SILAN MICROELECTRONICS JOINT-STOCK CO.,LTD
Rev: 1.0
16
2000.12.31
Silan
Semiconductors SC84510
PACKAGE OUTLINE
DIP-16-300-2.54
UNIT: mm
7.62
6.40
0.25
2.54
1.50
15 degree
3.30
5.08
3.51
19.4
0.46
HANGZHOU SILAN MICROELECTRONICS JOINT-STOCK CO.,LTD
Rev: 1.0
17
2000.12.31