DF4B
POS Cardholder Interaction Information (PCII)POS Cardholder Interaction Information is Kernel 2's mechanism for telling the reader that the cardholder still has something left to do on their own device before the transaction can complete - the canonical example being a second tap, when the first contactless interaction wasn't enough to finish whatever on-device confirmation the transaction required. It's related to the Card Transaction Qualifiers of the Visa-scoped Kernel 3 (9F6C) only in the broad sense that both tags exist to communicate device-interaction requirements back to the reader, even though the two are defined in different kernels and aren't interchangeable data. Scoped specifically to Mastercard PayPass (Kernel 2), DF4B is precisely the kind of field a reader's UX layer, not just its transaction-processing logic, needs to consume correctly: a reader that parses DF4B but doesn't actually prompt the cardholder for the required second interaction will leave a technically-valid-looking transaction stuck exactly where the card told it a human action was still needed. See EMV Contactless Book C-2.
Interactive decoder
Paste a hex value for this tag to decode it in your browser. Nothing is sent anywhere.
Binary (3): 000001
This tag is not a bitmap; the decoder shows a format-based interpretation.
Decoded example
Example value: 000001
Related tags
Properties
| Tag | DF4B |
|---|---|
| Name | POS Cardholder Interaction Information (PCII) |
| Format | Binary |
| Length | 3 bytes |
| Source | Card (ICC) |
| Templates | 77 |
| Books | EMV Contactless Book C-2 |
Frequently asked questions
- What is EMV tag DF4B?
- POS Cardholder Interaction Information is Kernel 2's mechanism for telling the reader that the cardholder still has something left to do on their own device before the transaction can complete - the canonical example being a second tap, when the first contactless interaction wasn't enough to finish whatever on-device confirmation the transaction required. It's related to the Card Transaction Qualifiers of the Visa-scoped Kernel 3 (9F6C) only in the broad sense that both tags exist to communicate device-interaction requirements back to the reader, even though the two are defined in different kernels and aren't interchangeable data. Scoped specifically to Mastercard PayPass (Kernel 2), DF4B is precisely the kind of field a reader's UX layer, not just its transaction-processing logic, needs to consume correctly: a reader that parses DF4B but doesn't actually prompt the cardholder for the required second interaction will leave a technically-valid-looking transaction stuck exactly where the card told it a human action was still needed. See EMV Contactless Book C-2.
- What format and length does EMV tag DF4B use?
- Tag DF4B uses the Binary format and is normally 3 bytes long.
- Is tag DF4B provided by the card or the terminal?
- Tag DF4B (POS Cardholder Interaction Information (PCII)) is provided by the Card (ICC).
Sources
- C-2-Kernel-2-V2.11-Final-June-2023, p. 406
Receive site updates
Subscribe to receive site updates directly to your email
We won't send spam. You can unsubscribe at any time.