> For the complete documentation index, see [llms.txt](https://developer.magtek.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://developer.magtek.com/hardware/card-readers/magnetic-stripe-readers/idynamo-5-gen-iii/documentation/developers-manuals/programmers-manual-.net-pcl/appendix-b-arqc-message-format.md).

# Appendix B	ARQC Message Format

This section gives the format of the ARQC Message delivered in the ARQC Message notification. The output is controlled by Property 0x68 – EMV Message Format. There are currently 2 selectable formats: Original and DynaPro. It is a TLV object with the following contents.

Original Format:

```
FD<len>/* container for generic data */ 
    DFDF25(IFD Serial Number)<len><val> 
    FA<len>/* container for generic data */
        <tags defined by DFDF02 >
            . Note: Sensitive Data cannot be defined in DFDF02
            .
        DFDF4D(Masked T2 ICC Data) 
        DFDF52 - Card Type Used
        F8<len>/* container tag for encrypted data */ 
                DFDF56(Encrypted Transaction Data KSN)<len><val>
                DFDF57(Encrypted Transaction Data Encryption Type)<val>

                FA<len>/* container for generic data */ 
                    DF30(Encrypted Tag 56 TLV, T1 Data)<len><val> 
                    DF31(Encrypted Tag 57 TLV, T2 Data)<len><val> 
                    DF32(Encrypted Tag 5A TLV, PAN)<len><val> 
                    DF35(Encrypted Tag 9F1F TLV, T1 DD)<len><val> 
                    DF36(Encrypted Tag 9F20 TLV, T2, DD)<len><val>
                    DF37(Encrypted Tag 9F61 TLV, T2 CVC3)<len><val> 
                    DF38(Encrypted Tag 9F62 TLV, T1,PCVC3)<len><val> 
                    DF39(Encrypted Tag DF812A TLV, T1 DD)<len><val> 
                    DF3A(Encrypted Tag DF812B TLV, T2 DD)<len><val> 
                    DF3B(Encrypted Tag DFDF4A TLV, T2 ISO Format)<len><val> 
                    DF40(Encrypted Value only of DFDF4A, T2 ISO Format)<len><val>
```

DynaPro Format:

```
F9<len>/* container for MAC structure and generic data */ 
    DFDF54(MAC KSN)<len><val>
    DFDF55(MAC Encryption Type)<len><val> 
    DFDF25(IFD Serial Number)<len><val> 
    FA<len>/* container for generic data */
        70<len>/*container for ARQC */ 
            DFDF53<len><value>/*fallback indicator */ 
            5F20<len><value>/*cardholder name */ 
            5F30<len><value>/*service code */ 
            DFDF4D<len><value>/* Mask T2 ICC Data */ 
            DFDF52<len><value>/* card type */ 
            F8<len>/*container tag for encryption */
                DFDF59(Encrypted Data Primitive)<len><Encrypted Data val (Decrypt data to read tags)>
                DFDF56(Encrypted Transaction Data KSN)<len><val> 
                DFDF57(Encrypted Transaction Data Encryption Type)<val> 
                DFDF58(# of bytes of padding in DFDF59)<len><val>
(Buffer if any to be a multiple of 8 bytes) 
CBC-MAC (4 bytes, always set to zeroes)
```

The Value inside tag DFDF59 is encrypted and contains the following after decryption:

```
                FC<len>/* container for encrypted generic data */
                                <tags defined by DFDF02 >
                                .

```


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