ANSWER: The contents of tag 9F39 indicate the transaction entry mode. The tag's possible values (and their meanings) are shown in the table below. This table comes directly from ISO-8583 and is not specific to ID TECH. (ISO-8583 is an industry standard, and these are the standard values and meanings.)
PAN entry mode
| PAN entry mode | Description |
| 00 | Unknown |
| 01 | Manual |
| 02 | Magnetic stripe |
| 03 | Bar code |
| 04 | OCR |
| 05 | Integrated circuit card (ICC). CVV can be checked. |
| 07 | Auto entry via contactless EMV. |
| 80 | Fallback to Magnetic Stripe |
| 90 | Magnetic stripe as read from track 2. CVV can be checked. |
| 91 | Auto entry via contactless magnetic stripe |
| 95 | Integrated circuit card (ICC). CVV may not be checked. |
| 99 | Same as original transaction. |