TT® FIX Order Routing

New Order List (E) Message

New Order List (E) Message

New Order List (E) Message

Purpose

Note New Order List (35=E) messages are supported in TT only by the EPEX exchange.

Defines a basket of multiple contracts and submits multiple individual orders in a single message.

For each New Order List (35=E) submitted, the exchange will either accept or reject all component orders in the list. Partial accepts or rejects will not be processed. No ack or reject is sent for the New Order List (35=E) message itself.

If the New Order List (35=E) message is accepted, then the FIX client will receive individual new order acknowledgment Execution Reports (39=0; 150=0) for each order in the list. The working component orders must then be managed individually as separate orders.

If the New Order List (35=E) message is rejected, then the FIX client will receive individual new order reject Execution Reports (39=8; 150=8) for each order in the list.

Note Time-in-force for the individual orders must be either IOC or FOK. No other TIFs are supported for component orders at this time.

Message Direction

From FIX client to TT FIX

Tag Directory

Click the links below to navigate to the documentation for that tag.

Supported Tags

Tag # Field Name Req’d Data type Comments
Component: <Standard Header>
Y 35=E (MsgType)
For additional information about this component group, consult the full documentation.
Tag # Field Name Req’d Data type Comments
8 BeginString Y String

FIX protocol version

The tag indicates the beginning of a new message. This tag must be the first tag in the message.

You must set the value to FIX.4.2 or FIX.4.4.

9 BodyLength Y int

Message length (in characters)

The value represents number of characters in the message following this tag up to, and including, the delimiter immediately preceding Tag 10 (CheckSum). This tag must be the second field in a message.

35 MsgType Y String

Type of message contained in the message body

This tag must appear third in the list of header tags.

Possible values include:

  • 0: Heartbeat
  • 1: Test Request
  • 2: Resend Request
  • 3: Reject
  • 4: Sequence Reset
  • 5: Logout
  • 8: Execution Report
  • 9: Order Cancel Reject
  • A: Logon
  • B: News
  • c: Security Definition Request
  • D: Order Single
  • d: Security Definition
  • e: Security Status Request
  • f: Security Status
  • F: Order Cancel Request
  • G: Order Cancel Replace Request
  • H: Order Status Request
  • Q: Don't Know Trade (Inbound Drop Copy only)
  • R: Quote Request
  • V: Market Data Request
  • W: Market Data Snapshot Full Refresh
  • X: Market Data Incremental Refresh
  • Y: Market Data Request Reject
  • AD: Trade Capture Report Request
  • AE: Trade Capture Report
  • AQ: Trade Capture Report Request Ack
49 SenderCompID Y String

ID for the FIX client, corresponding to the RemoteCompID specified for the user in TT User Setup

56 TargetCompID Y String

TT session identity

TT FIX does not validate this field. To guarantee session persistence, the FIX client must maintain the same value of this field for the life of the session.

You can use any value in this tag to identify the TT session for the FIX client. TT FIX will return this value in tag 49 (SenderCompID) in its responses.

50 SenderSubID N String

Unique ID for the message sender

For order routing messages, this tag overrides the exchange Operator ID configured in Setup.

57 TargetSubID C String

Unique ID for the message receiver.

Condition: If the Target Sub Id field has a value for the FIX Session in Setup, you must supply that value is this tag for a Logon (A) message.

116 OnBehalfOfSubID C String

Unique Trader ID

The value maps to the Alias field configured for a user in Setup.

Condition: Required when multiple users are associated with the account.

34 MsgSeqNum Y SeqNum

Message sequence number

142 SenderLocationID N string Specific message originator's location (i.e. geographic location and/or desk, trader)
43 PossDupFlag C Boolean

Whether the sequence number for this message is already used

Possible values include:

  • Y: Possible duplicate
  • N: Original transmission

Condition: Must send when a FIX client resends messages

Note: If 43=Y is present, TT will reject New Order Single (D), Order Cancel/Replace Request (G), New Order Multileg (AB), and Multileg Order Cancel/Replace (AC) messages with a Business Message Reject (j) message.

122 OrigSendingTime C UTCTimestamp

Original time of message transmission, when transmitting orders as the result of a resend request

Always expressed in UTC.

Condition: Required for resent messages

52 SendingTime Y UTCTimestamp

Time, in UTC, the message was sent.

66 ListID Y String

Unique identifier for list as assigned by institution, used to associate multiple individual orders. Uniqueness must be guaranteed within a single trading day. Firms which generate multi-day orders should consider embedding a date within the ListID <66> field to assure uniqueness across days.

Must be unique, by customer, for the day.

69 ListExecInst N String

Free format text message containing list handling and execution instructions.

73 NoOrders N NumInGroup

Indicates number of orders to be combined for average pricing and allocation.

11 ClOrdID Y String

Unique identifier for an Order as assigned by TT. Uniqueness is guaranteed within a single FIX trading session. Tag 11 values may be reused after the daily or weekly FIX session reset. Maximum length of the tag 11 is (20) characters.

67 ListSeqNo Y String

Sequence of individual order within list.

37 OrderId C string

Internal TT order key assigned to all orders submitted through any TT software.

The value remains constant for the life of an order.

Condition: Sent only for FIX Drop Copy OUT sessions when the Compliance Feed (Send original order/cancel/change messages and pending execution reports) setting is enabled for the session in TT Setup. The tag is ignored if sent on FIX Order Routing sessions.

Note: The value is unique per TT environment.

207 SecurityExchange C Exchange

Name of the market where the instrument trades.

TT FIX uses this value to identify the exchange that offers the security.

Possible values include:

  • AGGREGATOR
  • ALGO
  • ASE
  • ASX
  • B3
  • BitMEX
  • BrokerTec
  • CBOE
  • CboeFX_SW_NY
  • CBOT
  • CFE
  • CME
  • Coinbase
  • CoinFLEX
  • CurveGlobal
  • CZCE
  • DCE
  • DGCX
  • EEX
  • Eurex
  • Euronext
  • Fenics
  • FEX
  • HKEX
  • ICE
  • ICE_L
  • IDEM
  • INE
  • KCG
  • KRK
  • LME
  • LSE
  • MEFF
  • MEXDER
  • MX
  • MX
  • NDAQ_EU
  • NFI
  • NFX
  • OSE
  • SGX
  • TFEX
  • TFX
  • TOCOM

Condition: Required when Tag 100 (ExtDestination) is absent

OR
100 ExDestination C Exchange

Name of the sub-market where the instrument trades.

Execution destination for the order as defined by the institution

Some traders use this tag in place of Tag 207 (SecurityExchange) to identify the exchange.

ISO 10383 defines a comprehensive list of MIC codes.

Condition: Required when Tag 207 (SecurityExchange) is absent

Note: This tag can be included in messages sent from TT FIX Drop Copy sessions when the Compliance Feed (Send original order/cancel/change messages and pending execution reports) setting is enabled in Setup.

461 CFICode N String

Type of security using ISO 10962 standard, Classification of Financial Instruments (CFI code) values. ISO 10962 is maintained by ANNA (Association of National Numbering Agencies) acting as Registration Authority.

Note: For SPOT and CUR products, you must also specify the corresponding tag 167 (SecurityType) value.

Note: This tag can be included in messages sent from TT FIX Drop Copy sessions when the Compliance Feed (Send original order/cancel/change messages and pending execution reports) setting is enabled in Setup.

167 SecurityType Y String

Asset class of the instrument.

Possible values include:

  • CS: common stock
  • CUR: currency
  • FOR: Spot FX
  • FUT: future
  • MLEG: multi-leg
  • NDF: Non-Deliverable Forwards
  • NONE: No security type (Not valid for 35=c, e or V)
  • OPT: option
  • SPOT: EEX spot products
  • TBOND: treasury bond
  • INDEX: index
107 SecurityDesc N String

Security description.

Note: This tag can be included in messages sent from TT FIX Drop Copy sessions when the Compliance Feed (Send original order/cancel/change messages and pending execution reports) setting is enabled in Setup.

460 Product N int Product type associated with the security.

Possible values include:

  • 1: Agency
  • 2: Commodity
  • 3: Corporate
  • 4: Currency
  • 5: Equity
  • 6: Government
  • 7: Index
  • 8: Loan
  • 9: Money market
  • 10: Mortgage
  • 11: Municipal
  • 12: Other
  • 13: Financing
  • 14: Energy

Note: This tag can be included in messages sent from TT FIX Drop Copy sessions when the Compliance Feed (Send original order/cancel/change messages and pending execution reports) setting is enabled in Setup.

55 Symbol C String

Exchange-provided product symbol for the tradable product.

When specifying instruments for NewOrderMultileg (AB) and MultilegOrderCancelReplace (AC):

  • When submitting multi-leg instrument, set tag 55 to "[NA]".
  • When tag 54 (Side) is B or C, the value in tag 55 is ignored; the values in tag 600 (LegSymbol) and tag 624 (LegSide) in the LegInstrument group are used instead.

Condition: Not used when Tag 167 (SecurityType)=MLEG.

Note: This tag can be included in messages sent from TT FIX Drop Copy sessions when the Compliance Feed (Send original order/cancel/change messages and pending execution reports) setting is enabled in Setup.

48 SecurityID Y String

ID of the instrument.

Note: The combination of this tag and tag 22 (IDSource) must uniquely identify an instrument in the TT platform.

Note: This tag can be included in messages sent from TT FIX Drop Copy sessions when the Compliance Feed (Send original order/cancel/change messages and pending execution reports) setting is enabled in Setup.

22 IDSource Y String

Source for the value of tag 48 (SecurityID).

Possible values include:

  • 4: ISIN number
  • 5: RIC code
  • 8: Exchange symbol
  • 91: Ticker symbol
  • 96: TT security ID
  • 97: Alias
  • 98: Name
  • A: Bloomberg Code
  • H: Clearing House (Inbound Drop Copy only)
  • S: OpenFIGI ID
  • X: Series key

Note: The following values are only available for Inbound Drop Copy FIX clients.

Note: The following markets support RIC codes (22=5) for identifying futures, spreads and options instruments in tag 48 (SecurityID):

  • ASX
  • DGCX
  • CFE
  • CME
  • EEX
  • EUREX
  • Euronext
  • Hkex
  • ICE
  • ICE_L
  • LME
  • MEFF
  • MX
  • OSE
  • SGX
  • TFX
  • TOCOM

Note: The combination of this tag and tag 48 (SecurityID) must uniquely identify an instrument in the TT platform.

Note: This tag can be included in messages sent from TT FIX Drop Copy sessions when the Compliance Feed (Send original order/cancel/change messages and pending execution reports) setting is enabled in Setup.

454 NoSecurityAltID Y NumInGroup

Number of alternate security IDs in this repeating group

> 455 SecurityAltID Y String

Alternate ID for an instrument or security, typically for display purposes.

> 456 SecurityAltIDSource Y String

Alternate ID for an instrument or security

Possible values include:

  • 1: CUSIP number (sent only when provided by the exchange)
  • 4: ISIN number
  • 5: RIC code
  • 8: Exchange security ID
  • 91: Ticker Symbol
  • 92: TT product family ID (sent only for Security Definition (d) messages)
  • 93: TT product ID (sent only for Security Definition (d) messages)
  • 94: Alt Symbol (For ICE, the value is the "Cleared Alias" for the contract.)
  • 95: Clearport
  • 97: Alias
  • 98: Name
  • 99: Other (Set to instrument symbol if both product symbol and an instrument symbol are present in PDS and they are not the same.)
  • 100: Energy Identifier Code (EIC). Currently only used for the EPEX exchange.
  • A: Bloomberg Code
  • H: Clearing House (Inbound Drop Copy only)
  • S: OpenFIGI ID

Notes:

99 (Other) is not valid for order routing requests.

At this time, TT does not support FIX order routing or FIX market data subscriptions using CUSIP numbers for BrokerTec Treasury securities on CME.

> 16207 BloombergSecurityExchange C String

Name of the market where the instrument of the SecurityAltID (455) value trades.

200 MaturityMonthYear C MonthYear

Month and year the instrument reaches maturity in the format YYYYMM.

Note: If included, tag 541 (MaturityDate) will override this tag.

Condition: Required when Tag 541 is not specified and Tag 167 (SecurityType) is not MLEG or SPOT

Note: This tag can be included in messages sent from TT FIX Drop Copy sessions when the Compliance Feed (Send original order/cancel/change messages and pending execution reports) setting is enabled in Setup.

541 MaturityDate C LocalMktDate

Maturity date in format YYYYMMDD.

Note: This tag value overrides tag 200 (MaturityMonthYear) and tag 205 (MaturityDay), if they are also specified.

Condition: Required when Tag 200 is not specified and Tag 167 (SecurityType) is not MLEG or SPOT

Note: This tag can be included in messages sent from TT FIX Drop Copy sessions when the Compliance Feed (Send original order/cancel/change messages and pending execution reports) setting is enabled in Setup.

205 MaturityDay C DayOfMonth

Day of expiration for the instrument.

TT FIX uses this value and tag 200 (MaturityMonthYear) to specify the maturity date when tag 167 (SecurityType) is not MLEG and tag 18211 (DeliveryTerm) is not Month.

Whenever possible, tag 200 will match the Month & Year shown in TT Market Explorer, not the tag 541/Maturity Date field. In those cases where the MonthYear does not match, the value in tag 205 will be the day from tag 541, not necessarily the day associated with tag 200 MonthYear.

Range: 1-31

Note: If included, tag 541 (MaturityDate) will override this tag.

Condition: Required when multiple contracts exist for the same month

Note: This tag can be included in messages sent from TT FIX Drop Copy sessions when the Compliance Feed (Send original order/cancel/change messages and pending execution reports) setting is enabled in Setup.

18223 ContractYearMonth N String

Contract term in the form, YYYYMM

Condition: Sent when Tag 167 (SecurityType) is not MLEG

18211 DeliveryTerm C char

Term of delivery for the instrument.

TT FIX uses this value to identify contracts that do not have a monthly delivery term.

Possible values include:

  • A: Same day
  • B: Balance of month
  • C: End of Month
  • D: Day
  • E: Weekly
  • H: Hour
  • L: Balance of week
  • M: Month
  • N: Next day
  • P: Pack
  • Q: Quarterly
  • S: Seasonal
  • T: Weekend
  • U: Bundle
  • V: Variable
  • W: Week
  • X: Custom
  • Y: Year

The following values are only available for EPEX:

  • a=Quarter hour
  • b=Half hour
  • c=One hour
  • d=Two hour
  • e=Four hour
  • f=Eight hour
  • g=One plus two
  • h=Three plus four
  • i=Baseload
  • j=Peakload
  • k=Overnight
  • l=Extended peak

Note When Tag 18211 DeliveryTerm equals any value except 'M', 'Y' or 'Q', then you must specify the delivery day/date in Tag 205 MaturityDay or Tag 541 MaturityDate.

Condition: Required when both of the following are true:

  • The Security Definition indicates it is required.
  • The delivery term is not monthly.

Note: If you include this tag for instrument's that do not require it, TT FIX rejects the request.

Note: This tag can be included in messages sent from TT FIX Drop Copy sessions when the Compliance Feed (Send original order/cancel/change messages and pending execution reports) setting is enabled in Setup.

743 DeliveryDate N LOCALMKTDATE

Date for contract delivery

Note: This tag can be included in messages sent from TT FIX Drop Copy sessions when the Compliance Feed (Send original order/cancel/change messages and pending execution reports) setting is enabled in Setup.

201 PutOrCall C int

Whether the option represents a put or call

Possible values include:

  • 0: Put
  • 1: Call

Condition: Required when Tag 167 (SecurityType) is OPT

Note: This tag can be included in messages sent from TT FIX Drop Copy sessions when the Compliance Feed (Send original order/cancel/change messages and pending execution reports) setting is enabled in Setup.

202 StrikePrice C Price

Stirke price for an option

Condition: Required when Tag 167 (SecurityType) is OPT

Note: This tag can be included in messages sent from TT FIX Drop Copy sessions when the Compliance Feed (Send original order/cancel/change messages and pending execution reports) setting is enabled in Setup.

206 OptAttribute C char

Additional information about the option contract.

Condition: Required when both of the following are true:

  • Tag 167 (SecurityType) is OPT.
  • A version for the underlying instrument exists.

Note: This tag can be included in messages sent from TT FIX Drop Copy sessions when the Compliance Feed (Send original order/cancel/change messages and pending execution reports) setting is enabled in Setup.

762 SecuritySubType N String

Sub-type qualification or identification of the SecurityType

For example, an instrument with SecurityType(167)="MLEG" might use this tag to specify the name of the option or futures strategy, such as "Calendar", "Vertical", or "Butterfly".

For synthetic staged orders, i.e., HandlInst (21)=3 and SecurityType(167)="Synthetic", the TT FIX engine checks whether the instrument already exists and automatically creates the synthetic spread if the instrument does not exist.

Note: This tag can be included in messages sent from TT FIX Drop Copy sessions when the Compliance Feed (Send original order/cancel/change messages and pending execution reports) setting is enabled in Setup.

15 Currency C Currency

ISO-standard symbol for the instrument’s trading currency.

Note: This tag can be included in messages sent from TT FIX Drop Copy sessions when the Compliance Feed (Send original order/cancel/change messages and pending execution reports) setting is enabled in Setup.

38 OrderQty Y Qty Total order quantity
799 OrderAvgPx N Price Average price for a specific order
1 Account C String

Order-routing account

Note: Account names are stored as case-sensitive strings. Users must match case-sensitivity when using Tag 1 (Account).

Condition: Required for New Order Single (D) and Order Cancel/Replace Request (G) messages; optional, otherwise.

18 ExecInst C MultipleStringValue

Order execution instructions

Possible values include:

  • 2: Work (default)
  • 6: Participate don't initiate
  • G: All or none
  • S: Suspend
  • o: Cancel on connection loss (valid only for New Order Single (D) and New Order Multileg (AB) messages)
  • q: Release from suspension
  • X: Test request

Note: If you submit multiple values that include an unsupported value, TT FIX will choose the appropriate supported value.

To submit a new order in a “suspended” status, set this tag value to S.

To submit a normal order with cancel on disconnect, send "18=o 2"; the successful Execution Report (8) will return with 18=2.

To submit an order on hold with cancel on disconnect, send "18=o S". the successful Execution Report (8) will return with 18=S.

Note: The cancel on disconnect option is only supported in combination with '2' or 'S' and must be the 1st option in the list

Condition: Required when submitting a suspended order

864 NoEvents N NumInGroup

Number of entries in the event types repeating group

> 865 EventType N int

Type of event

Possible values include:

  • 5: Expiry date
  • 6: Last trading date

The following values are only available for EPEX:

  • 13:First delivery date
  • 14:Last delivery date
  • 101: First trading date
  • 102: SDAT first trading date
> 866 EventDate N LOCALMKtdATE

Date the event occurred

> 1145 EventTime N UTCTIMESTAMP

Note: This tag is only available for EPEX.

Specific time of event. Use in combination with EventDate <866>.

44 Price C Price

Limit price for limit orders

Condition: Required when Tag 40 (OrdType) is:

  • 2: Limit
  • 4: Stop Limit
54 Side Y char

Side of the order

Possible values include:

  • 1: Buy
  • 2: Sell
  • 3: Buy minus
  • 4: Sell plus
  • 5: Sell short
  • 6: Sell short exempt
  • 7: Undisclosed
  • 8: Cross
  • 9: Cross short
  • B: As Defined (FIX 4.4 only)
  • C: Opposite (FIX 4.4 only)

Note: If 54=B or 54=C, the order will be rejected, as these values are valid only for NewOrderMultileg (AB) and MultilegOrderCancelReplace (AC) messages.

40 OrdType Y char

Order type

Possible values include:

  • 1: Market
  • 2: Limit
  • 3: Stop
  • 4: Stop Limit
  • 5: Market On Close (MOC)
  • B: Limit On Close (LOC)
  • J: Market If Touched (MIT)
  • K: Market with Leftover as Limit
  • Q: Market Limit Market (MLM) with Leftover as Limit
  • S: Stop Market to Limit
  • T: Market to Limit (without Limit Price) If-Touched
  • U: Market to Limit If Touched (MLM-IT)
  • V: Market Close Today (reserved for future use)
  • W: Limit Close Today (reserved for future use)
  • p: Limit (post-only)
59 TimeInForce N char

How long an order remains active

Possible values include:

  • 0: Day (default, if not specified)
  • 1: Good Till Cancel (GTC)
  • 2: At The Opening (OPG)
  • 3: Immediate or Cancel (IOC)
  • 4: Fill Or Kill (FOK)
  • 5: Good Till Crossing
  • 6: Good Till Date
  • 7: At the Close
  • 8: Good through Crossing
  • 9: At Crossing
  • A: Auction
  • S: Morning At the Close
  • T: Afternoon At the Close
  • U: Night At the Close
  • V: Good in Session
  • W: Day Plus
  • X: Good Till Cancel Plus
  • Y: Good Till Date Plus

Notes: CME supports Immediate or Cancel (IOC) and Fill Or Kill (FOK) using the same Time in Force value (Tag 59=3).

If a TT FIX client submits a CME IOC (Tag 59=3) with a MinQty (Tag 110), the order will be treated by CME as a FOK.

To send an IOC, the FIX client should omit tag 110 from TT FIX New Order message.

Note: Although the TT FIX schema includes the new 'At the Close' TIFs for OSE (59=S, 59=T, and 59=U), at this time these values can not be used through FIX Order Routing or Drop Copy services. However, these values will be fully integrated in a future release.

Please monitor the TT Release Notes for announcements as to availability of these TIFs.

For more information about TIFs supported by exchanges, refer to Supported Order Types and TIFs in the Setup help.

Note: For the SAFEX exchange, you can use 59=6 (Good Til Date) in conjuction with tag 126 (ExpireTime) to submit a Good Til Time (GTT) order.

Note: EPEX only supports 3: Immediate or Cancel (IOC) and 4: Fill Or Kill (FOK).

432 ExpireDate C LocalMktDate

Date a Good Till Date order expires

Condition: Required when Tag 59 (TimeInForce) = 6 (Good Till Date)

126 ExpireTime N UTC_Timestamp

Time to stop working the order.

Notes:

  • Omit the tag to work the order until the market closes (GTC).
  • For the SAFEX exchange, you can use this tag in conjuction with 59=6 (Good Til Date) to submit a Good Til Time (GTT) order.
16556 TextA N String Value corresponding to the Text A field in TT widgets
16557 TextB N String Value corresponding to the Text B field in TT widgets
16558 TextTT N String Value corresponding to the Text TT field in TT widgets
16559 TextC N String Customer-defined text field not sent to exchange.
16601 EchoDC_01 N String

Customer-defined text field visible only to FIX client applications. The value is not sent to the exchange.

16602 EchoDC_02 N String

Customer-defined text field visible only to FIX client applications. The value is not sent to the exchange.

16603 EchoDC_03 N String

Customer-defined text field visible only to FIX client applications. The value is not sent to the exchange.

16604 EchoDC_04 N String

Customer-defined text field visible only to FIX client applications. The value is not sent to the exchange.

16605 EchoDC_05 N String

Customer-defined text field visible only to FIX client applications. The value is not sent to the exchange.

16606 EchoDC_06 N String

Customer-defined text field visible only to FIX client applications. The value is not sent to the exchange.

16607 EchoDC_07 N String

Customer-defined text field visible only to FIX client applications. The value is not sent to the exchange.

16608 EchoDC_08 N String

Customer-defined text field visible only to FIX client applications. The value is not sent to the exchange.

16609 EchoDC_09 N String

Customer-defined text field visible only to FIX client applications. The value is not sent to the exchange.

16610 EchoDC_10 N String

Customer-defined text field visible only to FIX client applications. The value is not sent to the exchange.

16631 EchoDC_11 N String

Customer-defined text field visible only to FIX client applications. The value is not sent to the exchange.

16632 EchoDC_12 N String

Customer-defined text field visible only to FIX client applications. The value is not sent to the exchange.

16633 EchoDC_13 N String

Customer-defined text field visible only to FIX client applications. The value is not sent to the exchange.

16634 EchoDC_14 N String

Customer-defined text field visible only to FIX client applications. The value is not sent to the exchange.

16635 EchoDC_15 N String

Customer-defined text field visible only to FIX client applications. The value is not sent to the exchange.

16636 EchoDC_16 N String

Customer-defined text field visible only to FIX client applications. The value is not sent to the exchange.

16637 EchoDC_17 N String

Customer-defined text field visible only to FIX client applications. The value is not sent to the exchange.

16638 EchoDC_18 N String

Customer-defined text field visible only to FIX client applications. The value is not sent to the exchange.

16639 EchoDC_19 N String

Customer-defined text field visible only to FIX client applications. The value is not sent to the exchange.

16640 EchoDC_20 N String

Customer-defined text field visible only to FIX client applications. The value is not sent to the exchange.

Component: <Standard Trailer>
Y For additional information about this component group, consult the full documentation.
Tag # Field Name Req’d Data type Comments
10 Checksum Y String

Unencrypted three-character checksum

This tag must always be the last field in a message (i.e. it serves, with the trailing <SOH>, as the end-of-message delimiter).