Lexicon MC-8 User manual

Software Version 2.0
Protocol Version:
Major Rev 1
Minor Rev 7
NOTE: The Parameter ID list in the rear pages of this document identifies specific commands to the version 2.00
software. However, the descriptions and information in the rest of the document apply to all versions of the
software currently released.
MC-8/MC-8B
Serial Protocol Definition

Lexicon MC-8 Serial Communications Protocol
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numbers and other worldwide patents issued and pending.
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© 2005 Harman International Industries, Incorporated. All rights reserved.
This document should not be construed as a commitment on the part of Harman International Industries,
Inc. The information it contains is subject to change without notice. Harman International Industries, 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 Service
Tel [phone]
Fax [phone] (Sales)
Fax [phone] (Service)
Lexicon Part No. 070-15332 Rev 1

Lexicon MC-8 Serial Communications Protocol
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1Documents 5
1.1 Change List 5
2Definitions 5
2.1 Protocol Version Cross-reference 5
3Abbreviations 5
4General Description 5
4.1 Physical Layer 6
4.2 Serial Port Driver 6
4.3 Errors 6
4.4 MC-8 Receive Buffer 6
4.5 MC-8 Hardware Verification 7
5Data Link Layer 7
5.1 Errors 7
6Application Layer 8
6.1 MC-8 Asynchronous Notification Packets 8
6.1.1 Wakeup Notification 8
6.1.2 Sleep Notification 8
6.1.3 Front Panel Display 8
6.1.4 MC-8 Parameter Notification by Id 9
6.2 Acknowledgment Packets 10
6.2.1 Acknowledge 11
6.2.2 No Acknowledge 11
6.3 Host Initiated Command Packets 11
6.3.1 Reset Unit 11
6.3.2 Restore Defaults 12
6.3.3 Get Custom Name 12
6.3.4 Set Custom Name 13
6.3.5 Host Wakeup 13
6.3.6 Host Sleep 14
6.3.7 Get Communication Configuration 14
6.3.8 Set Communication Configuration 15
6.3.9 Set Mute 15
6.3.10 Send Display String Command 16
6.3.11 MC-8 Get Parameter Definition by Id 17
6.3.12 MC-8 Set Parameter Value by Id 20
6.3.13 MC-8 Set Parameter Value by Id, No Run 21
6.3.14 MC-8 Get Unit Configuration 21
6.3.15 MC-8 Send IR Command 24
6.3.16 MC-8 Get Parameter Value by Id 25
6.3.17 MC-8 Set Parameter Notification by Id 25
6.3.18 MC-8 Parameter Get Value String by Id 26
6.3.19 MC-8 Clear All Parameter Notifications 27
6.3.20 MC-8 Get System Status 27
6.3.21 MC-8 Get Zone Status 29
6.3.22 MC-8 Set System Volume 30
6.3.23 MC-8 Set Main Balance 31
6.3.24 MC-8 Set Front/Back Balance 31
6.3.25 MC-8 Set Active Effect by Id 32

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6.3.26 MC-8 Set Zone2 Volume 32
6.3.27 MC-8 Set Zone2 Left/Right Balance 33
6.3.28 MC-8 Get Input Name by Id 33
6.3.29 MC-8 Set Input Name by Id 34
Appendix A Command Codes 35
Appendix B Error Codes 36
Appendix C MC-8 IR Codes 37
Appendix D MC-8 Input Ids 39
Appendix E Protocol Constants 39
Appendix F MC-8 Mode Ids 40
Application Notes and Examples 41
6.4 Box initializations: 41
6.4.1 MC-8: 41
6.4.2 HOST: 41
6.5 Simple System Control & System Status: 41
6.6 Examples: 41
6.6.1 MC-8 Get Unit Configuration 41
6.6.2 Send MC-8 IR Command Example 43
MC8 V2.00 Parameter ID List 44

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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-8.
070-15481 MC-8/MC-8B User Manual
1.1 Change List
9/2/05 Added Additional IR codes Appendix.
2 Definitions
User Parameter: A user changeable variable that stores a specific value that describes an
operating condition for the MC-8 system.
HOST: The device initiating or receiving the serial communication packets to/from the
MC-8.
MC-8: The Lexicon product receiving or transmitting the serial communication packets
to/from the HOST.
Nonvolatile RAM: The area of memory in an MC-8 that stores users adjustable parameters. The
Nonvolatile RAM is battery backed, to maintain values during MC-8 power down.
2.1 Protocol Version Cross-reference
All references to MC-8 shall be valid for both the MC-8 and SDP-5 products unless specifically
documented otherwise.
3 Abbreviations
SOP Start of Packet
EOP End of Packet
ACK Acknowledge
NAK No Acknowledge
FPD Front Panel Display
4 General Description
The intention of the MC-8 serial port and protocol communication is for an external connected HOST to
control and obtain status from the MC-8. The protocol has been designed to focus on two specific goals.
The first is HOST uploading and downloading of MC-8 configuration, and system/effect setups. The
second is HOST control of basic user adjustable parameters (i.e. input, volume, balance…).
CD VOL
Lexicon MC-8
HOST RS-232 Serial

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The MC-8 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 the MC-8. The MC-8 Protocol is a 3 layered system. The MC-8
serial protocol allows for the MC-8, or the HOST, to initiate a communication transaction. Most
transactions are initiated by the HOST. The MC-8 then responds to the HOST command with either a
response or acknowledgment packet. There are a few asynchronous notifications that the MC-8 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-8 Serial Protocol attempts to be as backward compatible with the MC-1 as possible. The basic
structure of the protocol has not changed.
4.1 Physical Layer
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.
4.2 Serial Port Driver
MC-8 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
4.3 Errors
The MC-8 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-8 will reset the transaction and begin to look for a
start of packet byte.
4.4 MC-8 Receive Buffer
The MC-8 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-8 will be ignored. Therefore, making the currently transmitted packet, if partially
transmitted invalid.
MC-8
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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4.5 MC-8 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-8 transmits a known test signal just following a power up. The MC-8
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-8 labeled “RS232”. The wraparound plug shorts pins
2 to 3, allowing for the MC-8 to receive the signal it is transmitting. Once installed, power cycle the MC-8
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.
5 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.
5.1 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-8 responds by transmitting a NAK packet with an error code
DC_ERR_INVALID_PACKET. The MC-8 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-8 will respond
by transmitting a NAK packet with an error code DC_ERR_INVALID_PACKET. The MC-8 then continues
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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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.
6 Application Layer
6.1 MC-8 Asynchronous Notification Packets
MC-8 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:
6.1.1 Wakeup Notification
By transmitting the Wakeup Notification, the MC-8 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-8.
6.1.1.1 Notification Packet Description
Application Header:
Command DC_WAKEUP 0x01
Data Count 0 0x00
Application Data:
N/A
6.1.1.2 Host Response
The MC-8 does not expect any response from the HOST.
6.1.2 Sleep Notification
By transmitting the Sleep Notification, the MC-8 indicates the unit is shutting down into a standby mode.
Because the hard power switch could be activated independently of the MC-8 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-8.
6.1.2.1 Notification Packet Description
Application Header:
Command DC_SLEEP 0x02
Data Count 0 0x00
Application Data:
N/A
6.1.3 Front Panel Display
The MC-8 will transmit the front panel display buffer following the update to the MC-8 front panel display.
The MC-8 front panel display is 2 X 20 ASCII character display. The HOST can enable transmission of
this notification message by sending Host Wakeup (6.3.5 page 13). To disable transmission the HOST

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can send Host Sleep (6.3.6 page 14). Transmission of the display buffer is asynchronous to other
host/MC-8 communication and will only transmit following the completion of any communication
exchanges in progress or pending.
6.1.3.1 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
6.1.3.2 Data Description
Line1 Data Type: Null (0x00) terminated ASCII character string.
Max Length: DISP_LINE_LENGTH defined in the Protocol Constants table
(Appendix E page 39)
Line2 Data Type: Null (0x00) terminated ASCII character string.
Max Length: DISP_LINE_LENGTH defined in the Protocol Constants table
(Appendix E page 39)
The MC-8 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
6.1.3.3 HOST Response
The MC-8 does not expect any response from the HOST.
6.1.4 MC-8 Parameter Notification by Id
The MC-8 will transmit parameter change notifications if they are enabled using the commands described
by the Set Parameter Notification by Id (6.3.17 page 25). If a parameter value is changed due to any
user action or system action the MC-8 will transmit the current value of the parameter that is changing.

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6.1.4.1 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…
6.1.4.2 Data Description
Same as the Set Parameter Value by ID: Data Description (6.3.12.2 page 20).
6.1.4.3 HOST Response
The MC-8 does not expect any response from the HOST.
6.1.4.4 Defaults
The following Parameters Notifications are Enabled in the MC-8 default state:
Parameter MC-8 Parameter Name
Current Mode HPARAM_MAIN_EFFECT
Main Zone Mute HPARAM_MAIN_MUTE
Main Zone Volume HPARAM_MAIN_VOLUME
Main Zone Balance HPARAM_MAIN_BALANCE
Main Zone Input Selection HPARAM_MAIN_INPUT
Zone 2 Input HPARAM_ZONE_INPUT
Zone 2 Volume HPARAM_ZONE_VOLUME
Zone 2 Balance HPARAM_ZONE_BALANCE
Zone 2 Mute HPARAM_ZONE_MUTE
Bass HPARAM_MAIN_BASS
Treble HPARAM_MAIN_TREBLE
Loudness HPARAM_MAIN_LOUDNESS
Tilt HPARAM_MAIN_TILT
Menu Background On/Off HPARAM_OSD_BACKGND
See V2.00 Parameter ID List (page 44) for the Parameter ID definitions.
6.2 Acknowledgment Packets
Acknowledge and No Acknowledge packets are used to communicate transmission, packet and data
validation status. Both the HOST and MC-8 can transmit and receive these packets.

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6.2.1 Acknowledge
6.2.1.1 Packet Description
Application Header:
Command DC_ACK 0xE0
Data Count 1 0x01
Application Data:
Data[0] Command nn
6.2.1.2 Data Description
Command:
DataType: Valid MC-8 command as defined in the Command Codes table
(Appendix A page 35).
6.2.2 No Acknowledge
6.2.2.1 Packet Description
Application Header:
Command DC_NACK 0xE1
Data Count 2 0x02
Application Data:
Data[0] Command nn
Data[1] ErrorCode nn
6.2.2.2 Data Description
Command:
DataType: Valid MC-8 command as defined in the Command Codes table
(Appendix A page 35).
ErrorCode:
DataType: Error code as defined in the Error Codes table (Appendix B page 36).
6.3 Host Initiated Command Packets
The MC-8 serial communication protocol has been designed to respond to the following commands as
described below. Each command is transmitted to the MC-8 with the identified parameters. If the
command is successfully received and processed by the MC-8, the unit will respond with the described
response packet or action.
6.3.1 Reset Unit
Commands the MC-8 to soft reset.

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6.3.1.1 Command Packet Description
Application Header:
Command DC_CMD_RESET 0x10
Data Count 0 0x00
Application Data:
N/A
6.3.1.2 MC-8 Response
The MC-8 will perform an internal reset. After reset, the MC-8 will go through a soft power-up
initialization. This includes transmitting the “Wakeup Notification Packet”. A soft reset does not
reinitialize the MC-8. Nonvolatile RAM is maintained.
6.3.2 Restore Defaults
Commands the MC-8 to restore the system and effect parameters to the factory defaults.
6.3.2.1 Command Packet Description
Application Header:
Command DC_CMD_RESTORE_DEFAULTS 0x13
Data Count 0 0x00
Application Data:
N/A
6.3.2.2 MC-8 Response
The MC-8 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-8 will go through a
soft power-up initialization. This includes transmitting the “Wakeup Notification Packet”.
6.3.3 Get Custom Name
Request to MC-8 for an effect definition. MC-8 will respond with “Custom Name Packet”.
6.3.3.1 Command Packet Description
Application Header:
Command DC_CMD_GET_CUST_NAME 0x2B
Data Count 0 0x00
Application Data:
N/A
6.3.3.2 Data Description
N/A
6.3.3.3 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

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6.3.3.4 Data Description
CustomName:
Data Type: Null (0x00) terminated ASCII character string.
Max Length: CUSTOM_NAME_LENGTH defined in the Protocol Constants table
(Appendix E page 39).
6.3.4 Set Custom Name
Sets the Custom Name that can be displayed when the unit powers up.
6.3.4.1 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
6.3.4.2 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 the Protocol Constants table
(Appendix E page 39).
6.3.4.3 MC-8 Response
If the custom name enable is TRUE then the custom name banner is display 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-8 will ACK when completed with this command.
6.3.4.4 Data Validation:
No data validation is done on the transmitted data.
6.3.5 Host Wakeup
By transmitting the Wakeup Notification, the Host indicates it has just “powered on” or reset and is ready
to receive MC-8 Notifications or Responses. The Host is assumed to be asleep upon power up of the
MC-8. Host status is maintained during standby.
6.3.5.1 Command Packet Description
Application Header:
Command HOST_WAKEUP 0x11
Data Count 0 0x00
Application Data:
N/A

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6.3.5.2 Data Description
N/A
6.3.5.3 MC-8 Response
The MC-8 will respond to this command with an ACK.
6.3.6 Host Sleep
By transmitting the Sleep command, the Host indicates it has just “powered down” and will no longer
respond to MC-8 Notifications. No Acknowledgment is expected. The Host is assumed to be asleep
upon power up of the MC-8. Host status is maintained during standby.
6.3.6.1 Packet Description
Application Header:
Command HOST_SLEEP 0x12
Data Count 0 0x00
Application Data:
N/A
6.3.6.2 Data Description
N/A
6.3.7 Get Communication Configuration
This command is a request to the MC-8 for the current communications configuration for the serial port
and protocol. The MC-8 responds to this command with a Communication Configuration Packet.
6.3.7.1 Command Packet Description
Application Header:
Command DC_CMD_GET_COM_CONFIG 0x2F
Data Count 0 0x00
Application Data:
N/A
6.3.7.2 Communication Configuration Response Packet
Application Header:
Command DC_RESP_COM_CONFIG 0x8C
Data Count 1 0x01
Application Data:
Data[0] Configuration Register 0 nn
6.3.7.3 Data Description
Data Word Bit Definition
0 0 Acknowledge Enable
0 1 Parameter Change Enable
Acknowledge Enable:
TRUE Indicates the MC-8 will transmit Acknowledge Notification to the Host.

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FALSE Indicates the MC-8 will not transmit any positive Acknowledge
Notification messages. The MC-8 will always transmit NAK error
notification messages.
Parameter Change Enable:
TRUE Indicates the MC-8 will transmit any parameter change Notification as
specified in the Parameter Change Notification Message.
FALSE Indicates the MC-8 will not transmit parameter change Notifications.
6.3.8 Set Communication Configuration
The Set Communication Configuration Command allows the serial port user to set up the various serial
port/ protocol configuration parameters.
6.3.8.1 Command Packet Description
Application Header:
Command DC_CMD_SET_COM_CONFIG 0x30
Data Count 1 0x01
Application Data:
Data[0] Configuration Register 0 nn
6.3.8.2 Data Description
Data Word Bit Definition
0 0 Acknowledge Enable
0 1 Parameter Change Enable
Acknowledge Enable:
TRUE Indicates the MC-8 will transmit Acknowledge Notification to the Host.
FALSE Indicates the MC-8 will not transmit any positive Acknowledge
Notification messages. The MC-8 will always transmit NAK error
notification messages.
Parameter Change Enable:
TRUE Indicates the MC-8 will transmit any parameter change Notification as
specified in the Parameter Change Notification Message.
FALSE Indicates the MC-8 will not transmit parameter change Notifications.
6.3.8.3 MC-8 Response
The data values transmitted will be copied over to the registers stored in nonvolatile RAM. The
MC-8 will respond with an ACK Packet.
6.3.9 Set Mute
The Set Mute Command message allows the RS232 users to set/clear the MC-8 mute state directly.
6.3.9.1 Command Packet Description
Application Header:
Command DC_CMD_SET_MUTE 0x31
Data Count 1 0x01
Application Data:
Data[0] Mute State nn

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6.3.9.2 Data Description
MUTE State:
Value Definition Description
0 UNMUTE
The user mute state is set to unmuted. The MC-8
may still be muted for other internal reasons.
1 USER MUTE
The system volume decrements by the specified
user amount as set in the OUTPUT LEVELS Menu.
2 FULL MUTE The system is fully muted.
6.3.9.3 MC-8 Response
The MC-8 will set the mute state according to the value transmitted. The MC-8 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.
6.3.9.4 Data Validation
The data value transmitted to the MC-8 will be verified as a valid value. If it is valid the MC-8 will
set/clear the mute and respond with an ACK Packet. If the data value is invalid the MC-8 will
respond with a DC_INVALID_DATA error NAK.
6.3.10 Send Display String Command
This command allows the Host to send a 40 character string to the MC-8 for display on the OSD and
Front Panel Display.
6.3.10.1 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
6.3.10.2 Data Description
Display Command Flags:
Word Bit Definition
0 0
FPD only: If set TRUE, the display string will only be sent to
the FPD device for display.
0 1 Undefined.
0 2 Undefined.
0 3 Undefined.
0 4 Undefined.
0 5 Undefined.
0 6 Undefined.
0 7 Undefined.

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Display String:
Data Type: Null (0x00) terminated ASCII character string.
Max Length: 40 Characters.
6.3.10.3 MC-8 Response
The display string is sent to the OSD and Front Panel Display. The MC-8 will ACK when
completed with this command.
6.3.10.4 Data Validation:
If a string length exceeds the 40 character maximum the string will be truncated before displaying
and the MC-8 will transmit a DC_NAK command with an error code DC_INVALID_DATA.
6.3.11 MC-8 Get Parameter Definition by Id
Request to MC-8 for a Parameter Definition by Parameter Id. MC-8 will respond with “MC-8 Parameter
Definition Packet”.
6.3.11.1 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
6.3.11.2 Data Description
ParamId:
Data Type: Unsigned 16 bit Integer
Max Value: Max Parameter Count as reported by the MC-8 Unit Configuration
Response Packet (6.3.14.2 page 22)
6.3.11.3 Data Validation:
If the ParamId is not a valid Id the MC-8 will respond with a NAK packet and error code DC_
INVALID_PARAM_ID.

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6.3.11.4 Parameter Definition Response Packet
The following Packet has been defined as follows for MC-8 V1.00. Future releases may modify
this definition.
Application Header:
Command MC_SYS_PARAM_DEF_PK
T 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
6.3.11.5 Data Description
ParamId:
Data Type: Unsigned 16 bit Integer
Max Value: Max Parameter Count as reported by the MC-8 Unit Configuration
Response Packet (6.3.14.2 page 22)

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ParamType:
Param Type Name ParamType
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
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.

Lexicon MC-8 Serial Communications Protocol
20
Read Only:
Data Type: Boolean
TRUE: Parameter is read only
FALSE: Parameter is writeable
6.3.12 MC-8 Set Parameter Value by Id
MC-8 Set Parameter by Id command sets the parameter value equal to the value sent in the command
packet and then runs the appropriate functional changes associated with changing the given parameter.
6.3.12.1 Command Packet Description
Application Header:
Command MC_CMD_SET_SYS_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…
6.3.12.2 Data Description
ParamId:
Data Type: Unsigned 16 bit Integer
Max Value: Max Parameter Count as reported by the MC-8 Unit Configuration
Response Packet (6.3.14.2 page 22)
ParamType:
Param Type Name ParamType
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