The acronym 1AQ1KR stands for 'One Arbitrary Question One Key Response'


TruRating is a system for collecting consumer ratings for services received via the payment process.

The Rating is collected by presenting a single question on the PIN entry device (PED) display during a POS transaction (which may be before payment) and getting a single numeric key press response (0-9) from any key on the keypad.

Questions are supplied as text so that merchants can adjust the questions according to their business requirements. The use of signed text (prompts) is therefore impractical.

The PIN Entry device must be able to perform a command (code-named “1AQ1KR”) that takes some arbitrary text (formatted according to the capabilities and requirements of the device) and waits for just one key press from the user (or times out) before returning the value of the chosen key.

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Figure 1: Normal processing of 1QA1KR

Protecting against fraudulent capture of PIN

A key concern over the use of free text during numeric data entry is the fraudulent capture of PINs. However it is not possible to enter a PIN in a single digit since all PINs must be at least 4 digits in length, and TruRating requires just a single key press response.

It could be possible to capture a PIN by executing a series of these commands in sequence, all with the identical text “Enter your PIN” displayed on the PED. One further specified feature of the 1AQ1KR command is that once a numeric key has been input, subsequent calls to the command within a 30 seconds timeout period will return immediately with an error code. This will effectively limit the caller to the maximum of a single numeric key press per transaction, thus preventing fraudulent PIN capture.

Language selection

It is recognised that many PED operating systems support the ability to switch between languages for a displayed prompt, by selecting some particular function key. The TruRating question is available from TruService in multiple languages – as requested by TruModule. It is therefore possible to match the selection of languages that the PED normally supports (e.g. default language of the PED).

In order to provide a consistent behavior of language selection in 1AQ1KR as in other prompt commands, it is proposed that if the key press returned identifies a function key that would normally invoke a switch in language, then the caller may re-issue the command using the appropriate question text and code table for the language selected.

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Figure 2: 1AQ1KR processing when language selection is supported