Lexicon MC-12HD User manual

Software Version 1.00
Protocol Version:
Major Rev 1
Minor Rev 6
MC-12HD
Serial Protocol Definitions

Lexicon MC-12HD Serial Communications Protocol
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numbers and other worldwide patents issued and pending.
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© 2006 Harman Specialty Group All rights reserved.
This document should not be construed as a commitment on the part of Harman Specialty Group. The
information it contains is subject to change without notice. Harman Specialty Group assumes no
responsibility for errors that may appear within this document.
Lexicon, Inc.
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Part No. 070-17383 | Rev 0
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Lexicon MC-12HD Serial Communications Protocol
Table of Contents
1Documents ..............................................................................................................................4
1.1 Change List........................................................................................................................4
2Definitions ...............................................................................................................................4
2.1 Protocol Version Cross-reference.....................................................................................4
3Abbreviations..........................................................................................................................4
4General Description................................................................................................................4
5Physical Layer.........................................................................................................................6
5.1 DB-9 RS232 Connector.....................................................................................................6
5.2 Serial Port Driver ...............................................................................................................6
5.3 Errors.................................................................................................................................6
5.4 Receive Buffer...................................................................................................................6
5.5 Hardware Verification........................................................................................................6
6Data Link Layer.......................................................................................................................7
6.1 Errors.................................................................................................................................7
7Application Layer....................................................................................................................8
7.1 Asynchronous Notification Packets...................................................................................8
7.1.1 Wakeup Notification ...................................................................................................8
7.1.2 Sleep Notification .......................................................................................................8
7.1.3 Front Panel Display....................................................................................................8
7.1.4 MC-12HD Parameter Notification by Id......................................................................9
7.2 Acknowledgment Packets ...............................................................................................10
7.2.1 Acknowledge............................................................................................................10
7.2.2 No Acknowledge ......................................................................................................11
7.3 Host Initiated Command Packets....................................................................................11
7.3.1 Reset Unit.................................................................................................................11
7.3.2 Restore.....................................................................................................................11
7.3.3 Get Custom Name....................................................................................................12
7.3.4 Set Custom Name....................................................................................................12
7.3.5 Host Wakeup............................................................................................................13
7.3.6 Host Sleep................................................................................................................14
7.3.7 Get Communication Configuration...........................................................................14
7.3.8 Set Communication Configuration ...........................................................................14
7.3.9 Set Mute...................................................................................................................15
7.3.10 Send Display String Command................................................................................16
7.3.11 MC-12HD Get Parameter Definition by Id................................................................16
7.3.12 MC-12HD Set Parameter Value by Id......................................................................18
7.3.13 MC-12HD Set Parameter Value by Id, No Run........................................................20
7.3.14 MC-12HD Get Unit Configuration.............................................................................20
7.3.15 MC-12HD Send IR Command..................................................................................23
7.3.16 MC-12HD Get Parameter Value by Id (MC-12HD)..................................................24
7.3.17 MC-12HD Set Parameter Notification by Id .............................................................25
7.3.18 MC-12HD Parameter Get Value String by Id...........................................................26
7.3.19 MC-12HD Clear All Parameter Notifications............................................................26
7.3.20 MC-12HD Get System Status ..................................................................................27
7.3.21 MC-12HD Get Zone2 Status....................................................................................29
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Lexicon MC-12HD Serial Communications Protocol
7.3.22 MC-12HD Set System Volume.................................................................................30
7.3.23 MC-12HD Set Main Balance....................................................................................30
7.3.24 MC-12HD Set Fader.................................................................................................31
7.3.25 MC-12HD Set Active Effect by Id.............................................................................31
7.3.26 MC-12HD Set Record Input .....................................................................................32
7.3.27 MC-12HD Set Zone2 Volume ..................................................................................32
7.3.28 MC-12HD Set Zone2 Left/Right Balance.................................................................33
7.3.29 MC-12HD Get Input Name by Id..............................................................................33
7.3.30 MC-12HD Set Input Name by Id ..............................................................................34
Appendix A: Command Codes...................................................................................................35
Appendix B: Error Codes............................................................................................................37
Appendix C: IR Codes .................................................................................................................38
Appendix D: Input IDs..................................................................................................................40
Appendix E: Protocol Constants................................................................................................41
Appendix F: Mode IDs .................................................................................................................42
Appendix G: Application Notes and Examples.........................................................................44
1Box initializations:................................................................................................................44
1.1 MC-12HD:........................................................................................................................44
1.2 HOST:..............................................................................................................................44
2Getting System Wide Status and Setup:............................................................................44
3Downloading the System Setup to the MC-12HD:.............................................................44
4Simple System Control & System Status:..........................................................................44
5Examples:..............................................................................................................................44
5.1 MC-12HD Get Unit Configuration....................................................................................44
5.2 Send MC-12HD IR Command Example..........................................................................46
6MC12HD V1.00 Parameter ID List........................................................................................46
7MC12HDEQ V1.00 Parameter ID List...................................................................................86
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Lexicon MC-12HD Serial Communications Protocol
1 Documents
The following documents should also be used with this document to understand how this protocol can be
used with an MC-12HD:
070-17555 Guide, User, MC12HD
1.1 Change List
1/11/06 New Document based on MC-12/MC-12B V5.0.
1/12/06 Updated Parameter Id Reference Table for MC12HD V 1.00 software.
2 Definitions
User Parameter: A user changeable variable that stores a specific value that describes an
operating condition for the MC-12HD system.
HOST: The device initiating or receiving the serial communication packets to/from the
MC-12HD.
MC-12HD: The Lexicon product receiving or transmitting the serial communication packets
to/from the HOST.
Nonvolatile RAM: An area of memory in an MC-12HD that stores user-adjustable parameters. The
Nonvolatile RAM is battery backed, to maintain values during power-down.
2.1 Protocol Version Cross-reference
All references to MC-12HD shall be valid for both the MC-12HD and SDP-40HD products unless
specifically documented otherwise.
3 Abbreviations
SOPStart of Packet
EOPEnd of Packet
ACKAcknowledge
NAKNo Acknowledge
FPDFront Panel Display
4 General Description
The intention of the MC-12HD serial port and protocol communication is for an external connected HOST
to control and obtain status from the MC-12HD. The protocol has been designed to focus on two specific
goals. The first is HOST uploading and downloading of MC-12HD configuration, and system/effect
setups. The second is HOST control of basic user adjustable parameters (i.e. input, volume, balance…).
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Lexicon MC-12HD Serial Communications Protocol
The MC-12HD 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-12HD. The MC-12HD Protocol is a 3 layered system. The MC-
12HD serial protocol allows for the MC-12HD, or the HOST, to initiate a communication transaction. Most
transactions are initiated by the HOST. MC-12HD then responds to the HOST command with either a
response or acknowledgment packet. There are a few asynchronous notifications that MC-12HD initiates
indicating system changes. After each transaction is initiated, the initiating device must wait for a
corresponding response before initiating the next transmission.
The 3 protocol layers are Physical, Data Link, and Application Layers.
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Lexicon MC-12HD Serial Communications Protocol
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-12HD 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-12HD will detect parity, framing and data overrun errors. If any physical layer errors are
detected, the complete packet is corrupted and the MC-12HD will reset the transaction and begin to look
for a start of packet byte.
5.4 Receive Buffer
The MC-12HD 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-12HD will be ignored, therefore making the currently transmitted packet, if partially
transmitted, invalid.
5.5 Hardware Verification
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-12HD transmits a known test signal just following a power up. The MC-
12HD monitors the serial port receivers while transmitting the test signal. If the signals are the same, the
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Lexicon MC-12HD Serial Communications Protocol
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-12HD labeled “RS232”. The wraparound plug
shorts pins 2 to 3, allowing for the MC-12HD to receive the signal it is transmitting. Once installed, power
cycle the MC-12HD and verify the following message is displayed on the FPD:
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
enclose 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.
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
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-12HD responds by transmitting a NAK packet with an error code
DC_ERR_INVALID_PACKET. The MC-12HD 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-12HD will
respond by transmitting a NAK packet with an error code DC_ERR_INVALID_PACKET. The MC-12HD
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.
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Lexicon MC-12HD Serial Communications Protocol
7 Application Layer
7.1 Asynchronous Notification Packets
MC-12HD 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
By transmitting the Wakeup Notification, MC-12HD 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-12HD.
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-12HD does not expect any response from the HOST.
7.1.2 Sleep Notification
By transmitting the Sleep Notification, MC-12HD indicates the unit is shutting down into a standby mode.
Because the hard power switch could be activated independently of the MC-12HD 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-12HD.
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-12HD will transmit the front panel display buffer following the update to the MC-12HD front panel
display. The MC-12HD front panel display is 2 X 20 ASCII character display. The HOST can enable
transmission of this notification message by sending Host Wakeup. To disable transmission the HOST
can send Host Sleep. Transmission of the display buffer is asynchronous to other host/MC-12HD
communication and will only transmit following the completion of any communication exchanges in
progress or pending.
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Lexicon MC-12HD Serial Communications Protocol
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 E Protocol Constants.
Line2 Data Type:Null (0x00) terminated ASCII character string.
Max Length:DISP_LINE_LENGTH defined in Appendix E Protocol Constants.
The MC-12HD 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-12HD does not expect any response from the HOST.
7.1.4 MC-12HD Parameter Notification by ID
MC-12HD will transmit parameter change notifications if they are enabled using the command described
in (MC12HD_Set_Parameter_Notification_By_Id). If a parameter value is changed due to any user action
or system action the MC-12HD will transmit the current value of the parameter that is changing.
7.1.4.1 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…
7.1.4.2 Data Description
Same as Parameter Set Data Description
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Lexicon MC-12HD Serial Communications Protocol
7.1.4.3 HOST Response
The MC-12HD does not expect any response from the HOST.
7.1.4.4 Defaults
The following Parameters Notifications are Enabled in the MC-12HD default state:
Parameter MC-12HD 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
7.2 Acknowledgment Packets
Acknowledge and No Acknowledge packets are used to communicate transmission, packet and data
validation status. Both the HOST and MC-12HD can transmit and receive these packets.
7.2.1 Acknowledge
7.2.1.1 Packet Description
Application Header:
Command DC_ACK 0xE0
Data Count 1 0x01
Application Data:
Data[0] Command nn
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Lexicon MC-12HD Serial Communications Protocol
7.2.1.2 Data Description
Command:
DataType:Valid MC-12HD command as defined in Appendix A Command Codes.
7.2.2 No Acknowledge
7.2.2.1 Packet Description
Application Header:
Command DC_NACK 0xE1
Data Count 2 0x02
Application Data:
Data[0] Command nn
Data[1] ErrorCode nn
7.2.2.2 Data Description
Command:
DataType:Valid MC-12HD 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-12HD serial communication protocol has been designed to respond to the following commands
as described below. Each command is transmitted to the MC-12HD with the identified parameters. If the
command is successfully received and processed by the MC-12HD, the unit will respond with the
described response packet or action.
7.3.1 Reset Unit
Commands the MC-12HD 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-12HD Response
The MC-12HD will perform an internal reset. After reset the MC-12HD will go through a soft power-up
initialization. This includes transmitting the “Wakeup Notification Packet”. A soft reset does not reinitialize
the MC-12HD. Nonvolatile RAM is maintained. While the unit is resetting, the front panel will show
“Configuring Please Wait”.
7.3.2 Restore
Commands the MC-12HD to restore the system and effect parameters to factory default settings.
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Lexicon MC-12HD Serial Communications Protocol
7.3.2.1 Command Packet Description
Application Header:
Command DC_CMD_RESTORE_DEFAULTS 0x13
Data Count 0 0x00
Application Data:
N/A
7.3.2.2 MC-12HD Response
The MC-12HD 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-12HD will go through a soft power-
up initialization. This includes transmitting the “Wakeup Notification Packet”.
7.3.3 Get Custom Name
Request to MC-12HD for the custom name. MC-12HD will respond with “Custom Name Packet”.
7.3.3.1 Command Packet Description
Application Header:
Command DC_CMD_GET_CUST_NAME 0x2B
Data Count 0 0x00
Application Data:
N/A
7.3.3.2 Data Description
N/A
7.3.3.3 Custom Name Response Packet
Application Header:
Command DC_RESP_CUST_NAME 0x89
Data Count Number of Characters in
CustomName + 1 nn
Application Data:
Data[0]- Data[DataCount-1] CustomName ch ch ch … 0x00
7.3.3.4 Data Description
CustomName:
Data Type:Null (0x00) terminated ASCII character string.
Max Length:CUSTOM_NAME_LENGTH defined in Appendix E Protocol Constants.
7.3.4 Set Custom Name
Sets the Custom Name that can be displayed when the unit powers up.
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Lexicon MC-12HD Serial Communications Protocol
7.3.4.1 Packet Description
Application Header:
Command DC_CMD_SET_CUST_NAME 0x2C
Data Count Number of characters in
CustomName + 2 nn
Application Data:
Data[0] CustomNameEnable nn
Data[1]-Data[DataCount-1] CustomName ch ch ch … 0x00
7.3.4.2 Data Description
CustomNameEnable:Enables/Disables the Custom Name Display.
DataType:Boolean
TRUE:CustomName Enabled
FALSE:CustomName Disabled
CustomName:
Data Type:Null (0x00) terminated ASCII character string.
Max Length:CUSTOM_NAME_LENGTH defined in Appendix E Protocol Constants.
7.3.4.3 MC-12HD Response
If the custom name enable is TRUE then the custom name banner is displayed on “power on”. If the
Custom Name Enable is FALSE the custom name is not displayed. The CustomName string is copied to
Nonvolatile RAM. The MC-12HD will send an ACK when completed with this command.
7.3.4.4 Data Validation:
No data validation is done on the transmitted data.
7.3.5 Host Wakeup
By transmitting the Wakeup Notification, the Host indicates it has just “powered on” or reset and is ready
to receive MC-12HD Notifications or Responses. The Host is assumed to be asleep upon power up of the
MC-12HD. Host status is maintained during standby.
7.3.5.1 Command Packet Description
Application Header:
Command HOST_WAKEUP 0x11
Data Count 0 0x00
Application Data:
N/A
7.3.5.2 Data Description
N/A
7.3.5.3 MC-12HD Response
The MC-12HD will respond to this command with an ACK.
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Lexicon MC-12HD Serial Communications Protocol
7.3.6 Host Sleep
By transmitting the Sleep command, the Host indicates it has just “powered down” and will no longer
respond to MC-12HD Notifications. No Acknowledgment is expected. The Host is assumed to be asleep
upon power up of the MC-12HD. Host status is maintained during standby.
7.3.6.1 Packet Description
Application Header:
Command HOST_SLEEP 0x12
Data Count 0 0x00
Application Data:
N/A
7.3.6.2 Data Description
N/A
7.3.7 Get Communication Configuration
This command is a request to the MC-12HD for the current communications configuration for the serial
port and protocol. The MC-12HD responds to this command with a Communication Configuration Packet.
7.3.7.1 Command Packet Description
Application Header:
Command DC_CMD_GET_COM_CONFIG 0x2F
Data Count 0 0x00
Application Data:
N/A
7.3.7.2 Communication Configuration Response Packet
Application Header:
Command DC_RESP_COM_CONFIG 0x8C
Data Count 1 0x01
Application Data:
Data[0] Configuration Register 0 nn
7.3.7.3 Data Description
Data Word Bit Definition
0 0 Acknowledge Enable
Acknowledge Enable:
TRUE Indicates the MC-12HD will transmit Acknowledge Notification’s to the Host.
FALSE Indicates the MC-12HD will not transmit any positive Acknowledge Notification
messages. The MC-12HD will always transmit NAK error notification messages.
7.3.8 Set Communication Configuration
The Set Communication Configuration Command allows the serial port user to set up the various serial
port/ protocol configuration parameters.
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Lexicon MC-12HD Serial Communications Protocol
7.3.8.1 Command Packet Description
Application Header:
Command DC_CMD_SET_COM_CONFIG 0x30
Data Count 1 0x01
Application Data:
Data[0] Configuration Register 0 nn
7.3.8.2 Data Description
Data Word Bit Definition
0 0 Acknowledge Enable
Acknowledge Enable:
TRUE Indicates the MC-12HD will transmit Acknowledge Notification’s to the Host.
FALSE Indicates the MC-12HD will not transmit any positive Acknowledge Notification
messages. The MC-12HD will always transmit NAK error notification messages.
7.3.8.3 MC-12HD Response
The data values transmitted will be copied over to the registers stored in nonvolatile RAM. The MC-12HD
will respond with an ACK Packet.
7.3.9 Set Mute
The Set Mute Command message allows the RS232 users to set/clear the MC-12HD mute state directly.
7.3.9.1 Command Packet Description
Application Header:
Command DC_CMD_SET_MUTE 0x31
Data Count 1 0x01
Application Data:
Data[0] Mute State nn
7.3.9.2 Mute State Data Description
Value Definition Description
0 UNMUTE The user mute state is set to unmuted. The MC-12HD may still
be muted for other internal reasons.
1 USER MUTE The system volume decrements by the specified amount set in
the OUTPUT LEVELS Menu.
2 FULL MUTE The system is fully muted.
7.3.9.3 MC-12HD Response
The MC-12HD will set the mute state according to the value transmitted. The MC-12HD may still be full
muted if other conditions require the audio path to be muted. This is only a direct access to the user mute
state.
7.3.9.4 Data Validation
The data value transmitted to the MC-12HD will be verified as a valid value. If it is valid the MC-12HD will
set/clear the mute and respond with an ACK Packet. If the data value is invalid the MC-12HD will respond
with a DC_INVALID_DATA error NAK.
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Lexicon MC-12HD Serial Communications Protocol
7.3.10 Send Display String Command
This command allows the Host to send a 40-character string to the MC-12HD for display on the OSD and
Front Panel Display.
7.3.10.1 Packet Description
Application Header:
Command DC_CMD_SET_DISPLAY_STR 0x33
Data Count Number of characters in the
DisplayStr + 2 nn
Application Data:
Data[0] DisplayFlags nn
Data[1]-Data[DataCount-1] DisplayStr ch ch ch … 0x00
7.3.10.2 Display Command Flags Data Description
Word Bit Definition
0 0 FPD only: If set TRUE, the display string will only be sent to the
FPD device for display.
Display String:
Data Type:Null (0x00) terminated ASCII character string.
Max Length:40 Characters.
7.3.10.3 MC-12HD Response
The display string is sent to the OSD and Front Panel Display. The MC-12HD will ACK when completed
with this command.
7.3.10.4 Data Validation:
If a string length exceeds the 40-character maximum the string will be truncated before displaying and the
MC-12HD transmit a DC_NAK command with an error code DC_INVALID_DATA.
7.3.11 MC-12HD Get Parameter Definition by Id
Request to MC-12HD for a Parameter Definition by Parameter Id. MC-12HD will respond with “MC-12HD
Parameter Definition Packet”.
7.3.11.1 Command Packet Description
Application Header:
Command MC_GET_PARAM_BY_ID 0x35
Data Count 2 0x02
Application Data:
Data[0] ParamId(LSB) nn
Data[1] ParamId(MSB) nn
7.3.11.2 Data Description
ParamId:
Data Type:Unsigned 16 bit Integer
Max Value: Max Parameter Count as reported by the MC-12HD Unit Configuration Response
Packet in MC-12HD Unit Configuration Response Packet
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Lexicon MC-12HD Serial Communications Protocol
7.3.11.3 Data Validation:
If the ParamId is not a valid Id the MC-12HD will respond with a NAK packet and error code DC_
INVALID_PARAM_ID.
7.3.11.4 Parameter Definition Response Packet
The following Packet has been defined as follows for MC-12HD V1.00. Future releases may modify this
definition.
Application Header:
Command MC_RESP_PARAM_DEF_PKT 0x8F
Data Count 110 0x6E
Application Data:
Data[0] ParamId(LSB) nn
Data[1] ParamId(MSB) nn
Data[2] ParamType nn
Data[3] MAX Value(LSB) nn
Data[4] MAX Value(MSB) nn
Data[5] MIN Value(LSB) nn
Data[6] MIN Value(MSB) nn
Data[7-27] CurrentValue[0 -20] nn nn nn…
Data[28]-Data[108] Parameter Path
ch ch ch …
0x00
Data[108] Read Only nn
7.3.11.5 Data Description
ParamId:
Data Type:Unsigned 16 bit Integer
Max Value: Max Parameter Count as reported by the MC-12HD Unit Configuration Response
Packet in MC-12HD Unit Configuration Response Packet
ParamType:
Param Type Name Param
Type ID Type Description Data
Size
(Bytes)
PARAM_TYPE_UINT8 0 Unsigned 8 bit integer(0 to 255) 1
PARAM_TYPE_UINT16 1 Unsigned 16 bit integer(0 to 65535) 2
PARAM_TYPE_CSTR8 2 Zero terminated string of 8 ascii characters 9
PARAM_TYPE_CSTR13 3 Zero terminated string of 13 ascii characters 14
PARAM_TYPE_UINT32 4 Unsigned 32 bit integer (0 to 4,294,967,295
) 4
PARAM_TYPE_BOOLEAN 5 Boolean( 0 to 1) 1
PARAM_TYPE_INT8 6 Signed 8 bit integer (-127 to 128) 1
PARAM_TYPE_BRANCH 7 Parameter Branch N/A
PARAM_TYPE_INT16 8 Signed 16 bit integer
(-32,767 to 32,768) 2
PARAM_TYPE_CSTR20 9 Zero terminated string of 20 ascii characters 21
Data: The data value transmitted is dependent on the ParamType, as described above. The
CurrentValue is always packed starting at the CurrentValue [0] byte in the packet. For
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Lexicon MC-12HD Serial Communications Protocol
multi-byte data, the values are packed LSB first(CurrentValue [0]) to MSB(CurrentValue
[0+(num bytes-1)]). For example: Setting a given signed 16 bit parameter to a value of -
300 the data array would be packed as follows:
Data[0] = 0xd4
Data[1] = 0xfe
Data[2 - 13] = don't care.
If a parameter's current value is a signed 16 bit parameter with a value of -3 the data
array would be packed as follows:
Data[0] = 0xfd
Data[1] = 0xff
Data[2 - 13] = don't care.
All signed values are in the 2's compliment format.
Max Value: This is a 16 bit value representing the maximum value for a parameter. Parameter values
exceeding the maximum will be limited to the maximum. This may be a signed or
unsigned value depending on the Parameter Type.
Min Value: This is a 16 bit value representing the minimum value for a parameter. Parameter values
exceeding the minimum will be limited to the minimum. . This may be a signed or
unsigned value depending on the Parameter Type.
Parameter Path:This is a zero terminated ASCII character string describing the parameter's name and
path in the units parameter tree structure.
Read Only: Data Type:Boolean
TRUE:Parameter is read only
FALSE:Parameter is writeable
7.3.12 MC-12HD Set Parameter Value by Id
Sets the parameter value equal to the value sent in the command packet, then runs the appropriate
functional changes associated with changing the given parameter.
7.3.12.1 Command Packet Description
Application Header:
Command MC_CMD_SET_PARAM_VALUE_BY_ID 0x36
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…
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Lexicon MC-12HD Serial Communications Protocol
7.3.12.2 Parameter Set Data Description
ParamId:
Data Type:Unsigned 16 bit Integer
Max Value:Max Parameter Count as reported by the MC-12HD Unit Configuration Response Packet in
MC12HD Unit Configuration Response Packet.
ParamType:
Param Type Name Param
Type
ID
Type Description Data
Size
(Bytes)
PARAM_TYPE_UINT8 0 Unsigned 8 bit integer(0 to
255) 1
PARAM_TYPE_UINT16 1 Unsigned 8 bit integer(0 to
65535) 2
PARAM_TYPE_CSTR8 2 Zero terminated string of 8
ASCII characters 9
PARAM_TYPE_CSTR13 3 Zero terminated string of 13
ASCII characters 14
PARAM_TYPE_UINT32 4 Unsigned 32 bit integer (0 to
4,294,967,295 ) 4
PARAM_TYPE_BOOLEAN 5 Boolean (0 to 1) 1
PARAM_TYPE_INT8 6 Signed 8 bit integer
(-127 to 128) 1
PARAM_TYPE_BRANCH 7 Parameter Branch N/A
PARAM_TYPE_INT16 8 Signed 16 bit integer
(-32,767 to 32,768) 2
PARAM_TYPE_CSTR20 9 Zero terminated string of 20
ASCII characters 21
Value:
The data value transmitted is dependent on the ParamType, as described above. The
Data Value is always packed starting at the Value[0] byte in the packet. For multi-byte
data, the values are packed LSB first (Value[0]) to MSB(Value[0+(num bytes-1)]). For
example: Setting a given signed 16 bit parameter to a value of -300 the data array would
pack as follows:
Value[0] = 0xd4
Value[1] = 0xfe
Value[2 - 13] = don't care.
All signed values are in the 2's compliment format.
7.3.12.3 Data Validation:
The ParamId must be a valid Parameter. The ParamType must be valid for the given ParamId. If either of
these condition is not true the MC-12HD will respond with a NAK packet and error code DC _
INVALID_PARAM_ID. The data value size cannot exceed the size of a given data type. A value that does
exceed the size of a give data type will be truncated to the appropriate size. The ParamType transmitted
must match the ParamType for the Parameter being transmitted, as per the Parameter Definition as
transmitted by the MC_SYS_PARAM_DEF_PKT . If the types do not match The MC-12HD will transmit a
NAK packet with a DC_INVALID_INPUT error code. The MC-12HD will transmit a NAK packet with a
DC_ERR_READ_ONLY error code for read only parameters.
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