Lexicon MC-12 V3.0 - SERIAL COMMUNICATIONS PROTOCOL DEFINITION REV... User manual

Lexicon, Inc.
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Serial Communications Protocol Definition
Project: MC-12/MC-12B
Updated: June 10, 2003
Software Version 3.0
Protocol Version:
Major rev 1
Minor rev 5
Lexicon, Inc.
3 Oak Park
Bedford, MA 01730-1413
[phone]

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Manufactured under license from Dolby Laboratories. “Dolby”, “Pro Logic”, and the double-D
symbol are trademarks of Dolby laboratories.
Lucasfilm and THX are trademarks or registered trademarks of Lucasfilm, Ltd.
© Lucasfilm, Ltd. & TM. Surround EX is a jointly developed technology of THX and Dolby
Laboratories, Inc. and is a trademark of Dolby Laboratories, Inc. All rights reserved. Used under
authorization.
Manufactured under license from Digital Theater Systems, Inc. U.S. Pat. No. 5,451,942;
5,956,674; 5,974,380; 5,978,762 and other world-wide patents issued and pending. “DTS”, “DTS-
ES Extended Surround” and “Neo:6” are trademarks of Digital Theater Systems, Inc. © 1996,
2000 Digital Theater Systems, Inc. All rights reserved.
“LOGIC7” and the LOGIC7 symbol are registered trademarks of Lexicon, Inc., a Harman
International Company.
© 2003 Lexicon, Inc. All rights reserved.
This document should not be construed as a commitment on the part of Lexicon, Inc. The
information it contains is subject to change without notice. Lexicon, Inc. assumes no responsibility
for errors that may appear within this document.
Lexicon, Inc.
3 Oak Park
Bedford, MA 01730-1413 USA
Tel [phone]
Fax [phone]
www.lexicon.com
Customer Support
Tel [phone]
Fax [phone] (Sales)
Fax [phone] (Service)
Lexicon Part No. 070-15859 REV 3

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1Documents 6
1.1 Change List 6
2 Definitions 6
2.1 Protocol Version Cross-reference 6
3 Abbreviations 6
4 General Description 7
5 Physical Layer 8
DB-9 RS232 Connector 8
5.2 Serial Port Driver 8
5.3 Errors 8
5.4 MC-12 Receive Buffer 8
5.5 MC-12 Hardware Verification (V1.10, Not Supported in MC-12 V1.00, V1.01) 8
6 Data Link Layer 9
6.1 Errors 9
7 Application Layer 10
7.1 MC-12 Asynchronous Notification Packets 10
7.1.1 Wakeup Notification (MC-12, MC-1) 10
7.1.2 Sleep Notification (MC-12, MC-1) 10
7.1.3 Front Panel Display (MC-12, MC-1) 10
7.1.4 MC-1 Parameter Change (MC-12, MC-1) 11
7.1.5 MC-12 Parameter Notification by Id (MC-12) 13
7.2 Acknowledgment Packets 14
7.2.1 Acknowledge (MC-12, MC-1) 14
7.2.2 No Acknowledge (MC-12, MC-1) 15
7.3 Host Initiated Command Packets 15
7.3.1 Reset Unit (MC-12, MC-1) 15
7.3.2 Restore (MC-12, MC-1) 15
7.3.3 MC-1 Send IR Command (MC-12, MC-1) 16
7.3.4 Get Unit Configuration (MC-12, MC-1) 16
7.3.5 Get System Status (MC-12, MC-1) 19
7.3.6 Get Zone 2 Status (MC-12, MC-1) 21
7.3.7 Get System Parameter Definition (MC-1) 22
7.3.8 Get System Parameter Values (MC-1) 22
7.3.9 Get Effect Definition by Id (MC-1) 22
7.3.10 Get Effect Parameter Definition (MC-1) 22
7.3.11 Get Effect Parameter Values (MC-1) 22
7.3.12 Get Custom Name (MC-12, MC-1) 22
7.3.13 Get Input Name by Id (MC-12, MC-1) 23
7.3.14 Get FPD Control Registers (MC-1) 23
7.3.15 Set System Parameter Values (MC-1) 24
7.3.16 Set Effect Parameter Values (MC-1) 24
7.3.17 Set Effect Name by Effect Id (MC-1) 24
7.3.18 Set System Volume (MC-12, MC-1) 24
7.3.19 Set Main Balance (MC-12, MC-1) 24
7.3.20 Set Front/Back Balance (MC-12, MC-1) 25
7.3.21 Set Active Effect by Id (MC-12, MC-1) 26
7.3.22 Set Record Input (MC-12, MC-1) 26

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7.3.23 Clear Record Input (MC-12, MC-1) 27
7.3.24 Set Zone2 Volume (MC-12, MC-1) 27
7.3.25 Set Zone2 Left/Right Balance (MC-12, MC-1) 28
7.3.26 Set Custom Name (MC-12, MC-1) 29
7.3.27 Set Input Name by Id (MC-12, MC-1) 29
7.3.28 Set FPD Control Registers (MC-1) 30
7.3.29 Host Wakeup (MC-12, MC-1) 30
7.3.30 Host Sleep (MC-12, MC-1) 31
7.3.31 Get Communication Configuration (MC-12, MC-1) 31
7.3.32 Set Communication Configuration (MC-12, MC-1) 32
7.3.33 Set Mute (MC-12, MC-1) 32
7.3.34 Set Output Level Adjustments (MC-1) 33
7.3.35 Send Display String Command (MC-12, MC-1) 33
7.3.36 MC-12 Get Parameter Definition by Id (MC-12) 34
7.3.37 MC-12 Set Parameter Value by Id (MC-12) 36
7.3.38 MC-12 Set Parameter Value by Id, No Run (MC-12) 38
7.3.39 MC-12 Get Unit Configuration (MC-12) 38
7.3.40 MC-12 Send IR Command (MC-12) 41
7.3.41 MC-12 Get Parameter Value by Id (MC-12) 41
7.3.42 MC-12 Set Parameter Notification by Id (MC-12) 42
7.3.43 MC-12 Parameter Get Value String by Id (MC-12) 43
7.3.44 MC-12 Clear All Parameter Notifications (MC-12) 44
7.3.45 MC-12 Get System Status (MC-12) 44
7.3.46 MC-12 Get Record Status (MC-12) 46
7.3.47 MC-12 Set System Volume (MC-12) 47
7.3.48 MC-12 Set Main Balance (MC-12) 47
7.3.49 MC-12 Set Front/Back Balance (MC-12) 48
7.3.50 MC-12 Set Active Effect by Id (MC-12) 48
7.3.51 MC-12 Set Record Input (MC-12) 49
7.3.52 MC-12 Set Zone2 Volume (MC-12) 50
7.3.53 MC-12 Set Zone2 Left/Right Balance (MC-12) 50
7.3.54 MC-12 Get Input Name by Id (MC-12) 51
7.3.55 MC-12 Set Input Name by Id (MC-12) 52
Appendix A Command Codes 53
Appendix B Error Codes 55
Appendix C DC-2, MC-1 IR-Codes 57
Appendix D MC-12 IR Codes 58
Appendix E MC-1 Input Id’s 59
Appendix F MC-12 Input Ids 59
Appendix G Protocol Constants 59
Appendix H MC-12 to MC-1 Effect Map 60
Appendix I MC-1 to MC-12 Effect ID Map 61
Appendix J MC-12 Mode Ids 62

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Application Notes and Examples 63
1.1 Box initializations: 63
1.1.1 MC-12: 63
1.1.2 HOST: 63
1.2 Getting System Wide Status and Setup: 63
1.1 Downloading the System Setup to the 63
1.3 MC-12: 63
1.4 Simple System Control & System Status: 63
1.5 Examples: 65
1.5.1 MC-12 Get Unit Configuration 65
1.5.2 Send MC-1 IR Command Example 66
1.5.3 Send MC-12 IR Command Example 67
1.6 MC12 V2.00 Parameter ID List 67

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1 Documents
The following documents should also be used with this document to understand how this protocol can be
used with an MC-12.
070-13227 MANUAL,OWNER'S,DC2
070-13278 MANUAL,OWNER'S,MC1
MC1/DC2 Serial Port Definition, Protocol Version 0.5
070-14773 Manual, Owner’s, MC12/MC12B
1.1 Change List
9/23/02 Added this paragraph.
9/23/02 Changed “7.9 MC12 V1.10 Parameter ID List” to “7.9 MC12 V2.00 Parameter ID List”
9/23/02 Updated Parameter Id Reference Table 7.9 MC12 V2.00 Parameter ID List for V2.00 s/w.
9/23/02 Updated Appendix J MC-12 Mode Ids for new V2.00 modes.
9/24/02 Updated 7.3.36.4 Parameter Definition Response Packet for correct CurrentValue length.
9/24/02 The range of the PARAM_TYPE_UINT32 parameter type has been corrected.
9/24/02 Updated Appendix H MC-12 to MC-1 Effect Map to reflect added modes in V2.0.
9/24/02 Updated Appendix I MC-1 to MC-12 Effect Map to reflect added modes in V2.0.
10/2/02 Updated Appendix D MC-12 IR Codes to reflect added button functionality for V2.0.
6/10/03 Updated Parameter Id Reference Table 7.9 MC12 V3.00 Parameter ID List for V3.00 s/w.
6/10/03 Updated Appendix J MC-12 Mode Ids for new V3.00 modes.
6/10/03 Updated 7.1.4 MC-1 Parameter Change (MC-12, MC-1) to reflect the disabled default state.
6/10/03 Added paragraph 7.1.5.4 Defaults to show parameters that are defaulted for notification.
2 Definitions
User Parameter: A user changeable variable that stores a specific value that describes an
operating condition for the MC-12 system.
HOST: The device initiating or receiving the serial communication packets to/from the
MC-12.
MC-12 ,MC-1,DC-2: The Lexicon product receiving or transmitting the serial communication packets
to/from the HOST.
Nonvolatile RAM: The area of memory in an MC-12 that stores users adjustable parameters. The
Nonvolatile RAM is battery backed, to maintain values during MC-12 power
down.
2.1 Protocol Version Cross-reference
All references to MC-12 shall be valid for both the MC-12 and SDP-40 products unless specifically
documented otherwise. All references to MC-1 shall be valid for the MC-1, DC-2 and SDP-3 products
unless specifically documented otherwise.
3 Abbreviations
SOP Start of Packet
EOP End of Packet

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ACK Acknowledge
NAK No Acknowledge
FPD Front Panel Display
4 General Description
The intention of the MC-12 serial port and protocol communication is for an external connected HOST to
control and obtain status from the MC-12. The protocol has been designed to focus on two specific goals.
The first is HOST uploading and downloading of MC-12 configuration, and system/effect setups. The
second is HOST control of basic user adjustable parameters.(i.e. input, volume, balance…)
The MC-12 uses simple notification, command, response and acknowledgment packets to have
communication transactions with a given HOST. This protocol is designed for point to point
communication between a HOST and MC-12. The MC-12 Protocol is a 3 layered system. The MC-12
serial protocol allows for the MC-12, or the HOST, to initiate a communication transaction. Most
transactions are initiated by the HOST. MC-12 then responds to the HOST command with either a response
or acknowledgment packet. There are a few asynchronous notifications that MC-12 initiates indicating
system changes. Each transaction initiated must wait for a corresponding response before initiating the next
transmission.
The 3 protocol layers are: Physical, Data Link, and Application Layers.
The MC-12 Serial Protocol attempts to be as backward compatible with the MC-1 as possible. This
document will try to inform the user/programmer of the consistencies and differences between the MC-1
protocol and the MC-12 protocol. The basic structure of the protocol has not changed. A number of
command/responses/notifications packets have been implemented exactly as they were in the MC-1. These
commands may not fully exercise the functionality of the MC-12 (i.e. Mc-1 has 8 inputs that have been
mapped to 8 of the 12 inputs on the MC-12, MC-1 IR codes are not the same as MC-12 IR codes) In the
case of these commands additional MC-12 commands have been added to fully implement the MC-12
functionality. In addition, some the internal structure of the MC-12 has forced the protocol to be unable to
support some MC-1 commands. These commands have been totally replaced with new commands that
provide more control over the MC-12 than was capable in the MC-1. (Parameter Set/Get commands)
Physical Layer (RS232)
Data Link Layer
Application Layer
CD VOL
Lexicon MC-12
HOST
Rs-232 Serial Link

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5 Physical Layer
5.1 DB-9 RS232 Connector
Note: The wiring requirements for a 9 pin to 9 pin serial connection, are a male to female straight through
cable.
5.2 Serial Port Driver
MC-12 serial port has been setup to operate as follows:
Operating Mode: Full Duplex
Baud rate: 19.2K baud
Data Size: 8 bits (1 byte)
Parity: Odd
Stop Bits: 1
Hardware Handshaking: None
5.3 Errors
The MC-12 will detect parity, framing and data overrun errors. If any of the physical layer errors are
detected, the complete packet is corrupted and the MC-12 will reset the transaction and begin to look for a
start of packet byte.
5.4 MC-12 Receive Buffer
The MC-12 has an internal receive buffer. The buffer is 256 Bytes and will transmit a NAK packet with an
error code of DC_ERR_BUFFER_FULL to the HOST if the buffer is full. If the buffer is full, all data
transmitted to the MC-12 will be ignored. Therefore, making the currently transmitted packet, if partially
transmitted invalid.
5.5 MC-12 Hardware Verification (V1.10, Not Supported in MC-12 V1.00, V1.01)
This test verifies the RS232 ports are working by comparing the transmitted signal (at pin 2) to the received
signal (at pin 3). The MC-12 transmits a known test signal just following a power up. The MC-12 monitors
the serial port receivers while transmitting the test signal. If the signals are the same, the test passes. In
order to test this circuit, RS232 Wraparound plug(s) are needed and must be installed at the female D9
connector(s) on the rear panel of the MC-12 labeled “RS232”. The wraparound plug shorts pins 2 to 3,
allowing for the MC-12 to receive the signal it is transmitting. Once installed, power cycle the MC-12 and
verify the following message is displayed on the FPD:
MC-12
COM1
Transmit Data
Receive Data
Ground
Host
Receive Data
Transmit Data
Ground
2
3
5
2
3
5
9 Pin D-Shell (female) 9 Pin D-Shell (male)
2
3
5
2
3
5
9 Pin D-Shell (male)
9 Pin D-Shell (female)

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SERIAL PORT A PASSED
SERIAL PORT B PASSED
This message is displayed for about 2 seconds before entering normal operating mode. If no messages are
displayed, then both wrap tests failed.
6 Data Link Layer
The data link layer is used to define a transmission packet. The layer appends a header and tail that
encloses the transmitted application packet data. The data link header will contain the start of packet byte
and count of bytes to follow. The data link tail will contain the end of packet byte.
6.1 Errors
If the number of DLL data bytes received is the same as the data count and an EOP has not been received,
the MC-12 responds by transmitting a NAK packet with an error code DC_ERR_INVALID_PACKET.
The MC-12 then continues to look for a SOP byte and will not process the erroneous application packet.
The HOST can use this as an indicator to retransmit the corrupted packet.
In addition, each byte of a packet must be received sequentially and within the INTER_PACKET_TIME. If
any of the bytes within a packet transmission exceeds the INTER_PACKET_TIME, the MC-12 will
respond by transmitting a NAK packet with an error code DC_ERR_INVALID_PACKET. The MC-12
then continues to look for a SOP byte and will not process the erroneous application packet. The HOST
can use this as an indicator to retransmit the corrupted packet.
Data Link Header:
Byte Number Description Value
First Byte(0) Start of Packet (SOP) 0xF1
Byte(1) DLL Data Count nn
Application Header:
Byte(2) Command nn
Byte(3)
APP Data Count (number of application data bytes to
Follow) nn
Application Data:
Byte(4) Data[0] nn
Byte(5) Data[1] nn
… Data[…] nn
Last Data Byte -1 Data[Data Count -1] nn
Data Link Tail:
Last Byte End of Packet (EOP) 0xF2

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7 Application Layer
7.1 MC-12 Asynchronous Notification Packets
MC-12 has been designed to transmit the asynchronous notification packets following these system
changes:
1. Power On
2. Entering Standby
3. Front Panel Display update
4. Parameter Value Changes.
The notification packets are defined as follows:
7.1.1 Wakeup Notification (MC-12, MC-1)
By transmitting the Wakeup Notification, MC-12 indicates the unit has just “powered on” or reset and is
ready to receive host commands. This notification is primarily for the HOST to know the status of the MC-
12.
7.1.1.1 Notification Packet Description
Application Header:
Command DC_WAKEUP 0x01
Data Count 0 0x00
Application Data:
N/A
7.1.1.2 Host Response
The MC-12 does not expect any response from the HOST.
7.1.2 Sleep Notification (MC-12, MC-1)
By transmitting the Sleep Notification, MC-12 indicates the unit is shutting down into a standby mode.
Because the hard power switch could be activated independently of the MC-12 system software, hard power
down will not be notified. Acknowledgment of the Sleep Notification is not required. This notification is
primarily for the HOST to know the operating status of the MC-12.
7.1.2.1 Notification Packet Description
Application Header:
Command DC_SLEEP 0x02
Data Count 0 0x00
Application Data:
N/A
7.1.3 Front Panel Display (MC-12, MC-1)
MC-12 will transmit the front panel display buffer following the update to the MC-12 front panel display.
The MC-12 front panel display is 2 X 20 ASCII character display. The HOST can enable transmission of
this notification message by sending Host Wakeup (7.3.29). To disable transmission the HOST can send
Host Sleep (7.3.30). Transmission of the display buffer is asynchronous to other host/MC-12

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communication and will only transmit following the completion of any communication exchanges in
progress or pending.
7.1.3.1 Notification Packet Description
Application Header:
Command DC_FPD 0x03
Data Count 42 0x2A
Application Data:
Data[0] - Data[20] Line1 ch ch ch… 0x00
Data[21] - Data[41] Line2 ch ch ch … 0x00
7.1.3.2 Data Description
Line1
Data Type: Null (0x00) terminated ASCII character string.
Max Length: DISP_LINE_LENGTH defined in Appendix G Protocol Constants.
Line2
Data Type: Null (0x00) terminated ASCII character string.
Max Length: DISP_LINE_LENGTH defined in Appendix G Protocol Constants.
The MC-12 includes 8 custom characters that are defined to display increments of a display block. (i.e.
Volume Bar) The custom characters are ASCII character codes 8E - 93(hex). The codes are used as
follows:
'8E' - empty cell
'8F' - left 1 bar
'90' - left 2 bars
'91' - left 3 bars
'92' - left 4 bars
'93' - full cell
7.1.3.3 HOST Response
The MC-12 does not expect any response from the HOST.
7.1.4 MC-1 Parameter Change (MC-12, MC-1)
MC-12 will transmit predetermined parameter change notifications. If a parameter value is changed due to
any user action or system action the MC-12 will transmit the current value of the parameter that is changing.
This command has been maintained for backward compatibility with MC-1. In order to maintain backward
compatibility, the MC-12 Parameters have been mapped to the MC-1 parameters as described in the
Supported System Parameters table listed below.
The MC-12 with s/w V3.0 will disable this notification by default.
This notifications can be enabled and disabled by using the commands described in 7.3.31 Get
Communication Configuration (MC-12, MC-1) and 7.3.32 Set Communication Configuration (MC-12,
MC-1).

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7.1.4.1 Notification Packet Description
Application Header:
Command DC_PARAM_CHG_MSG 0x04
Data Count 2 0x02
Application Data:
Data[0] ParamId nn
Data[1] Value nn
7.1.4.2 Data Description
ParamId:
Data Type: Unsigned 8 bit integer
Max: 255.
Value:
The Current Value for this system parameter.
Data Type: Unsigned 8 bit integer
Max: Set by the Max Value per the Parameter Definition response Packet for
the Parameter Id of this packet.
7.1.4.3 HOST Response
The MC-12 does not expect any response from the HOST.
7.1.4.4 Supported System Parameters
The following parameters will be supported by this Parameter Change Notification:
Parameter MC-12 Parameter
Name
MC-1
ParamId(V4.00)
Current Effect PROGRAM 1
Mute MUTE 3
System Volume VOLUME 5
Balance LR_BALANCE 6
Input Selection INPUT 7
Record/Zone 2 On/Off RECORD_ENABLED 18
Zone 2 Volume Z2_VOL 154
Zone 2 Balance Z2_BAL 156
Zone 2 Mute Z2_MUTE 157
Bass BASS 167
Treble TREBLE 168
Loudness LOUDNESS 169
Tilt TILT 174
Menu Background On/Off MENU_BKGND 190
Note: The Record/Zone 2 On/Off only applies to the MC-12 Record zone. The Zone 2 Volume, Zone 2
Balance and Zone 2 Mute only apply to the MC-12 Zone-2.
For Input Parameter Change Notifications the Input Value is a MC-12 to MC-1 input mapping, as shown in
Appendix F MC-12 Input Id's.

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7.1.5 MC-12 Parameter Notification by Id (MC-12)
MC-12 will transmit parameter change notifications if they are enabled using the command described in
7.3.42 (MC12_Set_Parameter_Notification_By_Id). If a parameter value is changed due to any user action
or system action the MC-12 will transmit the current value of the parameter that is changing.
7.1.5.1 Command Packet Description
Application Header:
Command MC_PARAM_NOTIFICATION_BY_ID 0x05
Data Count 24 0x18
Application Data:
Data[0] ParamId(LSB) nn
Data[1] ParamId(MSB) nn
Data[2] ParamType nn
Data[3-23] Value[0 -20]
nn nn
nn…
7.1.5.2 Data Description
Same as Paragraph 7.3.37.2
7.1.5.3 HOST Response
The MC-12 does not expect any response from the HOST.
7.1.5.4 Defaults
The following Parameters Notifications are Enabled in the MC-12 default state:

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Parameter MC-12 Parameter Name
Current Mode PARAM.MAIN.EFFECT
Main Zone Mute PARAM.MAIN.MUTE
Main Zone Volume PARAM.MAIN.VOLUME
Main Zone Balance PARAM.MAIN.BALANCE
Main Zone Input Selection PARAM.MAIN.INPUT
Zone 2 Input PARAM.ZONE.INPUT
Zone 2 Volume PARAM.ZONE.VOLUME
Zone 2 Balance PARAM.ZONE.BALANCE
Zone 2 Mute PARAM.ZONE.MUTE
Bass PARAM.MAIN.BASS
Treble PARAM.MAIN.TREBLE
Loudness PARAM.MAIN.LOUDNESS
Tilt PARAM.MAIN.TILT
Menu Background On/Off PARAM.OSD.BACKGND
See MC12 V3.00 Parameter ID List for the Parameter ID definitions.
7.2 Acknowledgment Packets
Acknowledge and No Acknowledge packets are used to communicate transmission, packet and data
validation status. Both the HOST and MC-12 can transmit and receive these packets.
7.2.1 Acknowledge (MC-12, MC-1)
7.2.1.1 Packet Description
Application Header:
Command DC_ACK 0xE0
Data Count 10x01
Application Data:
Data[0] Command nn
7.2.1.2 Data Description
Command:
DataType: Valid MC-12 command as defined in Appendix A Command Codes.

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7.2.2 No Acknowledge (MC-12, MC-1)
7.2.2.1 Packet Description
Application Header:
Command DC_NACK 0xE1
Data Count 20x02
Application Data:
Data[0] Command nn
Data[1] ErrorCode nn
7.2.2.2 Data Description
Command:
DataType: Valid MC-12 command as defined in Appendix A Command Codes.
ErrorCode:
DataType: Error code as defined in Appendix B Error Codes.
7.3 Host Initiated Command Packets
The MC-12 serial communication protocol has been designed to respond to the following commands as
described below. Each command is transmitted to the MC-12 with the identified parameters. If the
command is successfully received and processed by the MC-12, the unit will respond with the described
response packet or action.
7.3.1 Reset Unit (MC-12, MC-1)
Commands the MC-12 to soft reset.
7.3.1.1 Command Packet Description
Application Header:
Command DC_CMD_RESET 0x10
Data Count 0 0x00
Application Data:
N/A
7.3.1.2 MC-12 Response
The MC-12 will perform an internal reset. After reset the MC-12 will go through a soft power-up
initialization. This includes transmitting the “Wakeup Notification Packet”. A soft reset does not
reinitialize the MC-12. Nonvolatile RAM is maintained.
7.3.2 Restore (MC-12, MC-1)
Commands the MC-12 to restore the system and effect parameters to the factory defaults.
7.3.2.1 Command Packet Description
Application Header:
Command DC_CMD_RESTORE_DEFAULTS 0x13
Data Count 0 0x00
Application Data:
N/A

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7.3.2.2 MC-12 Response
The MC-12 will reset, clear any saved system and effect parameters in Nonvolatile RAM, and restore the
factory default system and effect parameters. After reset the MC-12 will go through a soft power-up
initialization. This includes transmitting the “Wakeup Notification Packet”.
7.3.3 MC-1 Send IR Command (MC-12, MC-1)
Transmits MC-1 IR command key codes to the MC-12.
This command has been maintained for backward compatibility to the MC-1. The MC-1 IR code
functionality has been mapped to the MC-12 IR code functionality as per the MC-1 to MC-12 IR code
table. MC-12 users should use the command described in 7.3.40 (MC-12_Send_IR_Command).
7.3.3.1 Command Packet Description
Application Header:
Command DC_CMD_IR 0x14
Data Count 1 0x01
Application Data:
Data[0] KeyCode nn
7.3.3.2 Data Description
KeyCode:
Data Type: Unsigned 8 bit integer
Valid Values: Appendix C MC-1 IR-Codes
7.3.3.3 MC-12 Response
The KeyCode is processed as a valid IR code. No acknowledgment will be sent from MC-12.
7.3.3.4 Data Validation
The KeyCode data will be verified as a legal IR code. If the Code is not valid the MC-12 will not respond.
7.3.4 Get Unit Configuration (MC-12, MC-1)
Request to MC-12 for its current unit configuration.
This command is supported for backward compatibility. MC-12 users should use the command described
in 7.3.39 (MC-12_Get_Unit_Configuration). MC-12 will respond with “Unit Configuration Packet”. The
HOST should use this information to determine if any information saved by the HOST is current.
7.3.4.1 Command Packet Description
Application Header:
Command DC_CMD_GET_CONFIG 0x15
Data Count 0 0x00
Application Data:
N/A

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7.3.4.2 MC-12 Unit Configuration Response Packet
Application Header:
Command DC_RESP_UNIT_CONFIG 0x80
Data Count 25 0x19
Application Data:
Data[0] ProductId nn
Data[1] Software Type nn
Data[2] Software Level nn
Data[3] Software Major Revision nn
Data[4] Software Minor Revision nn
Data[5] Protocol Major Revision nn
Data[6] Protocol Minor Revision nn
Data[7] N/A nn
Data[8] Total Number of Effects nn
Data[9] TimeStamp[0] ch
Data[10] TimeStamp[1] ch
Data[11] TimeStamp[2] ch
Data[12] TimeStamp[3] ch
Data[13] TimeStamp[4] ch
Data[14] TimeStamp[5] ch
Data[15] TimeStamp[6] ch
Data[16] TimeStamp[7] ch
Data[17] TimeStamp[8] ch
Data[18] TimeStamp[9] ch
Data[19] TimeStamp[10] ch
Data[20] TimeStamp[11] ch
Data[21] TimeStamp[12] ch
Data[22] TimeStamp[13] ch
Data[23] TimeStamp[14] ch
Data[24] TimeStamp[15] 0x00
7.3.4.3 Data Description
ProductId: This unsigned 8 bit value describes the product.
Product ID
Lexicon DC-2 1
Lexicon MC-1 2
JBL Synthesis SDP-3 3
Lexicon MC-12 4
JBL Synthesis SDP-40 5

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Software Type: An unsigned 8 bit value indicating the current configuration of the unit’s
software. The following table shows the values assigned to the available types:
SW Type
THX 1
AC3 2
DTS 3
COMPLETE 4
BOOTROM 5
Software Level: The following table shows the values assigned to the possible software levels:
SW Level
RELEASED 0
PRE_ALPHA 1
ALPHA 2
BETA 3
GAMMA 4
UNSUPPORTED 5
*Note: SW level indicates the status of the MC-12 internal application software.
Software Major Revision: An unsigned integer value indicating the unit’s major software version. The host
should use this information to determine if new effects, effect parameters, or
system parameters have been added or removed.
Software Minor Revision: An unsigned integer value indicating this unit’s minor software version.
Indicates the units software operation has changed but effects, effect parameters,
or system parameters have not changed.
Protocol Major Revision: An unsigned integer value indicating the serial communication protocol major
version. The host should use this value to determine if new commands,
notifications, or response packets have been added or deleted from this
specification.
Protocol Minor Revision: An unsigned integer value indicating the serial communication protocol minor
version. The host should use this value to determine if the existing commands,
notifications, or response packets have changed in this specification
Total Number of Effects: An unsigned integer value indicating the maximum number of effects available
for this version of software. This should be used to determine the maximum
EffectId used in the “Get Effect Definition Packet”, “Get Effect Parameter
Definition Packet”, “Set Effect Name Packet”, and “Set Effect Parameter
Values Packet”.
TimeStamp: Is a null terminated ASCII text string describing the build date and time of the
current software build. The Format of this text string is:
“yy/mm/dd(sp)hh:mm”
yy- is the last two digits of the year (i.e. year 1999 = 99, year 2000 = 00)
mm - is the month

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dd- is the day
(sp) - is an ASCII space character (0x20)
hh - is the hour
mm - is the minute
7.3.5 Get System Status (MC-12, MC-1)
Request to MC-12 for its current system status. MC-12 will respond with “System Status Packet”.
This command has been maintained for backward compatibility with MC-1. In order to maintain backward
compatibility, the MC-12 Parameters have been mapped to the MC-1 parameters as described in each Data
Description. MC-12 users should be using the command described in 7.3.45 (MC-12_Get_System_Status).
7.3.5.1 Command Packet Description
Application Header:
Command DC_CMD_GET_SYS_STATUS 0x16
Data Count 0 0x00
Application Data:
N/A
7.3.5.2 System Status Response Packet
Application Header:
Command DC_RESP_SYS_STATUS 0x81
Data Count 10 0x0A
Application Data:
Data[0] System Volume nn
Data[1] Current Input nn
Data[2] Current Effect Id nn
Data[3] Current Input Sample Rate nn
Data[4] Current Input Format nn
Data[5] Mute Active nn
Data[6] Effect Bypass nn
Data[7] Left/Right Balance nn
Data[8] Front/Back Balance nn
Data[9] Video Synch nn
7.3.5.3 Data Description
System Volume:
Data Type: Unsigned 8 bit integer.
Maximum Value: 92
Conversion: 0 = -80 dB
92 = +12 dB
Current Input:
Data Type: Unsigned 8 bit integer
Definition/Conversion: Appendix F MC-12 Input Ids
Current Effect Id:
Data Type: Unsigned 8 bit integer

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Definition/Conversion: Appendix_H_MC-12_Effect_Ids
Current Input Sample Rate:
Data Type: Unsigned 8 bit integer.
SAMPLE RATE
RATE_UNKNOWN 0
RATE_44 1
RATE_48 2
RATE_88 3
RATE_96 4
Current Input Format:
Data Type: Unsigned 8 bit integer.
DATA STREAM TYPE
DATA_TYPE_UNKNOWN 0
DATA_TYPE_BYPASS 1
DATA_TYPE_ANALOG 2
DATA_TYPE_PCM 3
DATA_TYPE_DD 4
DATA_TYPE_DTS 5
DATA_TYPE_NOISE 6
Mute Active:
Data Type: Boolean.
TRUE: System Mute is Active
FALSE: System is unmuted.
Effect Bypass:
Data Type: Boolean
TRUE: Effect Bypass is Active
FALSE: Effect Bypass is Inactive
Left/Right Balance:
Data Type: Unsigned 8 bit integer.
Maximum Value: 32
Conversion: 0 = Left
16 = Center
32 = Right
Front/Back Balance:
Data Type: Unsigned 8 bit integer.
Maximum Value: 32
Conversion: 0 = Front
16 = Center
32 = Back
Video Synch:
Data Type: Boolean.
TRUE: MC-12 has detected Video Sync for current video input
FALSE: MC-12 can not detect Video Sync for the current video input