Figure 6-1 - Typical Transaction Sequence
### About the Status LEDs DynaFlex provides four RGB LEDs directly below the chip card insertion slot (see section 1.8 About DynaFlex Components), numbered LED1 through LED4, which report the device’s current operating status. * The meaning of each LED depends on the device’s operating mode. See section 6.1 About Operating Modes and Table 6-1 below. Most of the time, operators will check the device’s status using the LEDs when it is in Active Mode while the device is not performing a transaction. * LED colors have specific meanings, as described in Table 6-2. They are based on international conventions for traffic light colors, with additional colors reserved for unusual / special cases. * LED blinking patterns have specific meanings as well, as described in Table 6-3. A blinking LED generally means the device is actively doing something to change the state that the LED is indicating and solid indicates a persistent state that would require an operator or cardholder to take action to change. One major exception is a device-wide functional failure state, such as a tamper state, where all LEDs flash urgently to call the attention of an advanced operator to intervene. In this manual, specific combinations of LED colors and blinking patterns are described in more detail in the sections where they are relevant and use the same icons in the tables below to indicate color and blinking patterns. For example, information about how the LEDs show the device’s connection status is in section 4.3 Connecting to a Host. ## Table - DynaFlex LED Allocation| In This Context | LED1 | LED2 | LED3 | LED4 |
| Active Mode, not armed for a tap transaction | Power | Connection | Reserved | Card Read Result |
| Active Mode, armed for a tap transaction |
Armed for Tap |
Tap Read Progress |
Tap Read Progress |
Card Read Result |
| Device-wide failure | During major failures (such as tamper), LED1-LED4 report the nature of the failure based on the most likely steps required to resolve it. | During major failures (such as tamper), LED1-LED4 report the nature of the failure based on the most likely steps required to resolve it. | During major failures (such as tamper), LED1-LED4 report the nature of the failure based on the most likely steps required to resolve it. | During major failures (such as tamper), LED1-LED4 report the nature of the failure based on the most likely steps required to resolve it. |
| Color | Means |
| Stop or stopped Example: LED1 is red. Stop using device: Battery is about to run out of charge. |
| Wait or waiting
Example: LED2 is yellow. Waiting for host to connect. |
| Go, going, or went
Example: LED2 is green. Host is connected, device is ready to Go. |
Other Colors |
Reserved |
| Color | Means |
Solid | Solid LEDs generally require an operator or cardholder to take action to change the state the LED is reporting.
Example: Host is connected. Cardholder or host would have to disconnect. Example: Host is disconnected. Host would have to initiate connection. |
| Blinking | Blinking LEDs generally mean the device is in the process of doing / attempting something. Blink duty cycle and blink period are generally selected to show urgency or ongoing progress through a series of steps.
Example: Device is attempting to connect to the WLAN access point. |
| Short time | LEDs sometimes light for a short time to indicate some process has ended (success or failure) and the device is going to transition to another state soon. Example: Successful card read. |
| Status Icon | Meaning |
| Device’s Active Connection is set to USB, and the device has successfully established a USB communication connection with the host. |
| Solid indicates WLAN is not configured |
| Blinking indicates error connecting to wireless access point. Refer to Connection Status Page Error Code for information on error. |
| Blinking to indicate the device is connecting to a wireless access point |
| Device’s Active Connection is set to 802.11 wireless, and the device is connected to a wireless access point. The number of bars indicates the strength of the signal the device is receiving from the wireless access point (commonly known as RSSI). |
| TLS security on the 802.11 wireless connection is Disabled (red open padlock) TLS security on the 802.11 wireless connection is Enabled (black closed padlock) |
| Solid indicates TLS security on the 802.11 wireless connection is Enabled and connected. |
| Blinking indicates error during TLS Handshake. Refer to Connection Status Page Error Code for information on error. |
| Socket Protocol (WebSocket, MQTT) is active or connected |
| Solid indicates Socket Protocol (WebSocket, MQTT) is inactive or disconnected |
| Blinking indicates error connecting Socket Protocol (WebSocket, MQTT). Refer to Connection Status Page Error Code for information on error. |
| Battery is fully charged. |
| Status Icon | Meaning |
| Battery is OK, between 20% and 95% charged. |
| Battery is low, between 10% and 20% charged. |
| Battery is critically low, between 3% and 10% charged. |
| Battery is empty, below 3% charged. |
| Battery is charging. |
Figure 6-2 - Welcome Page Examples
The device may display text other than “Welcome” when it is Active / idle under certain conditions: * **OFFLINE / Tampered:** indicates the device has detected an attempt to tamper with it (for example, physical tampering, out-of-spec temperature range, electrical attack). If this occurs, remove the device from service and set it aside in a secure location for possible forensic analysis, and contact the manufacturer or your reseller for support. This mode can only be reset in the manufacturing facility. * **OFFLINE / Tamper Not Active:** indicates the device’s tamper detection system is not activated. The device is not configured properly. If this occurs, remove the device from service and contact the manufacturer or your reseller for support. * **OFFLINE / Security Not Activated:** indicates the device’s data security features have not been activated. The device is not configured properly. If this occurs, remove the device from service and contact the manufacturer or your reseller for support. * **OFFLINE / Security Activated:** indicates the device is ready to have keys injected. If this occurs, remove the device from service and contact the manufacturer or your reseller for support. * **OFFLINE / HW Missing:** indicates the device can not detect one or more of its installed modules. This may indicate a mechanical or electrical failure. If this occurs, remove the device from service and contact the manufacturer or your reseller for support. * **OFFLINE / Keys Missing:** indicates the device is missing one of the encryption keys that are critical to its data security systems. The device needs to have keys properly injected. If this occurs, remove the device from service and contact the manufacturer or your reseller for support. * **OFFLINE:** without any clarifying text indicates the device is not ready for normal operation. ### **Device Information Page** While powering up, the display briefly shows a page of information about the device, including the installed firmware part numbers and versions and other identifying information. To determine a device’s PCI certification status, compare the contents of this screen to the device’s listing on [www.pcisecuritystandards.org,](http://www.pcisecuritystandards.org/) *Approved PTS Devices*. Note that in PCI listings, lowercase “x” is a wildcard meaning ‘any single character.’Figure 6-3 - Device Information Screen
To view details pertinent to the device’s PCI certification status on WLAN enabled devices - including the installed firmware part numbers and versions as well as other identifying information (see Figure 6-4) complete the following actions: While on the Welcome screen, press the Pushbutton and hold for 3 beeps to access to Settings menu, then select Firmware , and Main to return to the Welcome screen, select Back and Exit.Figure 6-4 - Device Information Screen for WLAN device
#### Connection Status Page In addition to the icons at the top of the display, WLAN enabled devices have a WLAN Status screen that reports more details about the device’s 802.11 wireless (see Figure 6-5). To access it, while on the Welcome screen, press the Pushbutton and hold for 3 beeps to get to the Settings menu, then select Connection and WLAN Settings, and WLAN Status. To return to the Welcome screen, select Back and Exit.Figure 6-6 – SoftAP Mode screen
### About Sounds DynaFlex products have a beeper (audible signal) that provides feedback to operators and cardholders about the internal state of the device: * The device sounds one short beep after it has successfully read a contactless tap, and the cardholder can safely remove the card or device from the contactless landing zone. * The device emits short beeps continuously when a transaction is complete, but the card is still present in the insertion slot. * The device emits two beeps when reading a card or contactless payment device to indicate a read error occurred. * The device sounds two beeps when an operator cancels a pending EMV transaction. The device provides an internal setting the host can use to adjust the global system volume. The device does not provide an interface to change the volume setting directly via buttons or the touchscreen. If the device is too quiet or too loud: * Make sure the device is ordered from the manufacturer with the desired volume setting. * Check to see whether the host software you are using provides a feature to check and/or adjust the volume setting. * If the host software does not provide that feature, request help from the development team that built the host software to check / change the volume setting. For details, see *DYNAFLEX AND DYNAFLEX PRO PROGRAMMER'S MANUAL (COMMANDS)*. ### Power Management #### About Power This device incorporates a built-in Lithium-ion rechargeable battery, which requires very little maintenance. It is not subject to “charge memory” and therefore does not require deep discharge cycles to restore its charge capacity like many other battery technologies. When properly powered through its USB port, the device powers on automatically, remains powered on provided the host does not put it in USB Suspend mode, and draws power both for operation and for recharging the battery (see section 6.6.3 How to Charge the Battery). While charging, the device consumes more power from the USB connection than when the battery is fully charged. The device stops charging the battery when it determines it is optimally full, to prevent overcharging. If the device is not connected to USB power, or if the USB connection does not provide enough power, the device powers itself using the rechargeable battery. When the battery discharges to a critically low level, the device powers down automatically. It is critically important to not allow the device’s main battery to remain completely discharged any longer than absolutely necessary, or the device’s security features may lock it down and require a return to the manufacturer to reset. For information about how to prevent this from occurring during handling and storage, see section 3.2 Handling to Avoid Accidental Tamper. To prevent this from occurring during regular use: * Do not allow the device’s main battery remain completely discharged for prolonged periods of time, and ideally do not allow it to ever reach 0%. Create a charging schedule that recharges the battery well before it is fully depleted. * When the device is not connected to USB power, preserve the battery’s charge when it is not in use by putting the device into Sleep mode or powering it off completely (see section 6.6.4 How to Power On / Wake Up from Standby Mode / Power Off). The device’s rechargeable battery is designed to last hundreds of charging cycles, but with time and / or with use, its charge capacity will naturally degrade. Following the recommendations in this section will maintain the battery’s charge capacity for as long as possible. ### How to Check Battery Level Reserved. ### How to Charge the Battery {% hint style="warning" %} Per UL requirements, the device is designed to not recharge its internal battery when the external temperature is below 0°C or above 40°C. {% endhint %} DynaFlex products have an onboard rechargeable battery to supply their own power when they are not powered through the USB-C port. The battery must be periodically recharged by connecting the device to the optional charging cradle, or to a USB port or stand-alone USB charger. Both the charging cradle and the device require a USB power supply that can provide at least 500mA @ 5V, optimally 1A @ 5V. To charge the device without an optional charging cradle, connect it to a USB charger or a USB host as described in section 4.3.2 How to Connect DynaFlex Products to a Host or Charger via USB. For best results, use the cable that is included with the device; it includes shielding at both ends to reduce interference. When charging, make sure the device is receiving enough power from the USB connection (battery level should increase even when device is in use). A full recharge cycle for a completely drained battery depends on how it is being charged. From a host USB port at 500mA, full charge takes approximately 7 hours. From a dedicated wall charger or charging cradle, a full charge make take as little as 4 hours. After connecting the device to a power source, make sure the LEDs indicate the device is charging (see section 6.3 About the Status LEDs). To charge the device in the optional charging cradle *for power only (no USB communication)*: * Make sure the charging cradle is properly installed and is receiving USB power. See section 4.4.4 How to Mount the Charging Cradle. * Place the device in the charging cradle with the charging contacts pointing into the charging cradle and the device’s face pointing toward the ceiling as shown in Figure 4-5 on page 25. * Check the device’s LEDs to make sure it is charging. For important information about the device’s power systems, optimal charging methods during regular use, optimal handling and storage, and other information about keeping the device’s power systems in the best possible condition, see section 3.2 Handling to Avoid Accidental Tamper and section 6.6.1 About Power. ### How to Power On / Wake Up from Standby Mode / Power Off To power on the device, press and hold the pushbutton for one second, or connect the device to USB power. After powering on, devices with touchscreens show a page of information about the device, then transition to showing the Welcome page or custom graphics, if they are configured to do so. For more information about custom graphics, see *DynaFlex and DynaFlex Pro Programmer’s Manual (COMMANDS)*. To power off the device, disconnect the device from USB power. To reset the device, see section **How to Force Reset.** If all LEDs are off, the device is in Powered Off mode, USB Suspend mode, or Standby mode. For details about reading the status of the device with LEDs, see section 6.1 About Operating Modes and section **About the Status LEDs.** #### How to Force Reset To force the device to reset, power it off then power it on again (see section **How to Power On / Wake Up from Standby Mode / Power Off**). Alternatively, you may use a small tool such as a paperclip to carefully press the recessed switch inside the small hole on the bottom of the device (see section **About DynaFlex Components** on page 12). The host may also reset the device by sending the Reset Device command (see section 8 **Developing Custom Software)**. The device also automatically powers off if the rechargeable battery reaches a level that is low enough that the device may not be able to complete a transaction (see section 6.6.7 About Battery Warnings and Automatic Reset). ### How to Turn Bluetooth LE Advertising On and Off Reserved. ### About Battery Warnings and Automatic Reset Reserved ### About USB Suspend When the device is connected to a host via USB (see section **How to Connect DynaFlex Products to a Host or Charger via USB**), the host and its operating system can use standard USB functions to put the device into USB Suspend mode to conserve power (see section 6.1 About Operating Modes). This generally occurs when there is no software running on the host that has an active USB connection with the device. When the device goes into USB Suspend mode, the device’s display and LEDs turn off. When the host wakes up the device from USB Suspend, the device returns to normal operation. It is possible to configure a Windows host to not suspend the device by editing the registry. Open HKEY\_LOCAL\_MACHINE\SYSTEM\CurrentControlSet\Enum\USB\VID\_0801\&PID\_2020, then open the folder with the device’s serial number inside that folder and open the Device Parameters folder inside that. Set the value of EnhancedPowerManagementEnabled the setting, physically disconnect and re-connect the device to the host.Figure 6-7 - Example Card Swipe Screens
Figure 6-8 - Swiping a Magnetic Stripe Card
#### How to Insert Contact Chip Cards To insert contact chip cards, follow these steps: * Wait for the device to display an action prompt, or, if the solution is designed to respond to cardholder actions that occur while the device is idle, such as swiping, inserting, or tapping a card or electronic payment device, or pressing the touchscreen, initiate the transaction by performing one of those actions instead of waiting. In these cases, the device may automatically and rapidly pass through several of the steps below without requiring cardholder interaction. * Devices with a touchscreen show on-screen text and buttons (see Figure 6-9 below for examples). * Devices with or without a touchscreen show the transaction status using the LEDs. If the host has directed the device to enable the contactless interface, LED1 lights solid green and all other LEDs are off, per EMV standards, to indicate it is ready for a tap, swipe, or insert. If the host has directed the device to disable the contactless interface, the device continues to show idle statuses on LED1 and LED2. * All devices report detailed transaction status to the host, and host software may report that information to operators so they can guide cardholders through the transaction (for example, “swipe, insert, or tap your card now please”). * Locate the chip card insertion slot on the face of the device, as shown in Figure 6-10. * Orient the chip card so the chip faces the cardholder, toward the touchscreen or contactless landing zone and the LEDs. * Insert the chip card into the slot, then push gently on the card until it stops. There should not be any substantial resistance until the chip card is fully inserted. * Wait for a prompt that the device has successfully read the card, then remove the card. * The device turns LED4 green for a brief time. * The device beeps once. * If the device has a display: * The device shows Processing. * The device shows Please Wait and/or AUTHORIZING PLEASE WAIT . * If the transaction requires a signature, the device prompts for a signature (see section 6.9.9 How to Use Signature Capture). * The device shows REMOVE CARD . * The device shows THANK YOU . * The device ends the transaction and reports the transaction status to the host. * As a reminder to the cardholder to remove the card, the device beeps continuously until the card is removed. * If the device can not communicate with the chip card: * The device lights LED4 red for a short time. * The device beeps twice. * Devices with a display show FAILED , then if the card is still in the slot, then Thank You, then return to the idle page (see section **Welcome Page / Active Idle Page**). * The device ends the transaction and notifies the host that the transaction failed. If this occurs, the host software may choose to retry the transaction (for example, with different payment types enabled) or revert to prompting the operator to enter card data manually (see section How to Enter Card Information Manually). * As a reminder to the cardholder to remove the card, the device double-beeps continuously until the card is removed. Immediately after the user inserts a chip card, the device disables the option to use the contactless interface. If the cardholder needs to revert to a contactless card or device for payment while a transaction is in process, the operator should cancel the transaction and start again.Figure 6-9 - Example Card Insertion Screens
Figure 6-10 - Inserting a Chip Card
#### How to Tap Contactless Cards / Devices To tap a contactless card or smartphone, follow these steps: * Wait for the device to display an action prompt, or, if the solution is designed to respond to cardholder actions that occur while the device is idle, such as swiping, inserting, or tapping a card or electronic payment device, or pressing the touchscreen, initiate the transaction by performing one of those actions instead of waiting. In these cases, the device may automatically and rapidly pass through several of the steps below without requiring cardholder interaction. * Devices with a touchscreen show on-screen text and buttons (see Figure 6-11 below for examples).\\ * Devices with or without a touchscreen show the transaction status using the LEDs. LED1 lights solid green and all other LEDs are off, per EMV standards, to indicate it is ready for a tap (or swipe or insert, if the host has enabled those interfaces for this transaction). * All devices report detailed transaction status to the host, and host software may report that information to operators so they can guide cardholders through the transaction (for example, “please tap your card now”). * If the cardholder is using an electronic payment device, such as a smartphone, make sure the payment device has NFC turned On and has a payment app configured to process transactions. For details, see the documentation provided by the smartphone manufacturer and payment app publisher. * Briefly hold the card, smartphone, or other contactless payment device over the contactless landing zone, indicated by the EMVCo Contactless Indicator symbol on the device’s face (see Figure 6-11). Because each smartphone model may have its NFC antenna placed differently, the ideal tap position may vary by make and model. For example, Samsung users may need to center the phone on the contactless landing zone, while Apple users may need to tap the top of the phone on the contactless landing zone. * Wait for a prompt that the device has successfully read the card, smartphone, or other contactless payment device, then remove it from the contactless landing zone. * The device quickly lights the second LED green to show it is processing, then lights the third LED green to show it has successfully read the tap, then lights the fourth LED green to show the read is complete (see Figure 6-13). * The device beeps once. * If the device has a display: * The device may show PROCESSING . * The device shows REMOVE CARD . * If the transaction requires a signature, the device prompts for a signature (see section **How to Use Signature Capture**). * The device shows THANK YOU . * The device ends the transaction and reports the transaction status to the host. * If the device can not communicate with the card, smartphone, or other contactless payment device: * The device ends the transaction. * The device lights LED4 red for a brief time. * The device beeps twice. * Devices with a display show INSERT, SWIPE, OR TRY ANOTHER CARD , then Thank You, then return to the idle page (see section 6.4.1 Welcome Page / Active Idle Page). * The device notifies the host that the transaction failed. If this occurs, the host software may choose to retry the transaction (for example, with different payment types enabled) or revert to prompting the operator to enter card data manually (see section **How to Enter Card Information Manually**).Figure 6-11 - Example Contactless Transaction Screens
Figure 6-12 - Tapping a Contactless Card / Smartphone
Figure 6-13 - Tap Read Is Complete
#### How to Scan Barcodes To scan a barcode, follow these steps: * Make sure you are using a DynaFlex model that includes a barcode reader, indicated by QR code markings on the face of the device surrounding the barcode reader lens (see section 1.8 About DynaFlex Components). * If the barcode being scanned is not on a self-illuminated source such as a smartphone, make sure there is enough ambient light for the camera to read the barcode. In low light conditions, the barcode reader will only be able to read self-illuminated sources. * In some solutions, the operator may have to perform an operation in the host software to enable the barcode reader, or to start a transaction with the barcode reader enabled. * Wait for the device, the host, or the operator to prompt for a barcode read: * Devices with a display show the prompt SCAN BARCODE . * The device lights the barcode reader indicator LED next to the barcode reader lens. * Hold the barcode in front of the barcode reader camera: * If possible, use the light from the barcode reader indicator LED to align the barcode within the barcode reader’s field of view, which extends 16 degrees above / below and 21 degrees to the left/right of a line perpendicular to the barcode reader lens. * Hold the barcode as close as 1 inch from the lens. For smaller barcodes, the device will read immediately. If it does not, gradually pull back to up to 14 inches from the lens until the device reports a successful read. Larger barcodes must be far enough away from the device that the whole barcode is within the camera’s field of view; if a large barcode is too close, the barcode reader can only see a zoomed in portion of the barcode. * Do not tilt the barcode more than 60 degrees from parallel to the device’s face. * Wait for the device or the host to report the barcode has been read successfully: * Devices with a display will no longer show the prompt SCAN BARCODE . * The device beeps once. * The device turns off the barcode reader indicator LED.Figure 6-14 – Scanning a Barcode
#### How to Enter Card Information Manually Devices with touchscreen displays provide support for starting a transaction that immediately prompts the operator or cardholder to enter card data manually. Manual entry can be useful in the following situations: * **· As a last-resort form of transaction fallback:** * o The cardholder swiped during a transaction that had one or more card interfaces enabled, but the device could not read card data. * o The cardholder inserted a chip card during a transaction that had one or more card interfaces enabled, but the device could not read card data and could not fall back to swipe. * · In card not present transactions, including merchant locations where cardholders do not have their card, in telephone call centers, and so on. In these cases, the operator uses the device to keep sensitive data out of the merchant’s domain, for compliance / security reasons. To enter card information manually, follow these steps. For every prompt below, press the Enter button after entering data to move to the next step, or press the Backsp button to delete data that has already been entered but stay on the same step, or press the Cancel button to completely end the transaction: * The operator starts a transaction, specifying manual card entry, optionally specifying a transaction amount and cash back amount. If the solution is designed to respond to cardholder actions that occur while the device is idle, such as pressing the touchscreen, the operator may initiate the transaction by performing one of those actions instead of initiating the transaction from the host. * The device shows a numeric keypad and a prompt to enter Card Number (see Figure 6-15). Enter the card number and press the Enter button. If the device double-beeps when pressing the button and does not proceed to the next step, the PAN is not valid. The device may be configured to enable MOD10 validation, which makes sure the card number passes a validity check to prevent errors during entry. It is also possible you have entered too many or too few PAN digits. Double-check the card number and use the BackSP button to correct any errors, then press Enter. * The device shows a numeric keypad and a prompt to enter Exp Date (MMYY)v(see Figure 6-16). Enter the expiration date on the card and press the Enter button. * The device shows a numeric keypad and a prompt to enter CVV/CVC/Card ID. Enter the card verification code / value, then press the Enter button. This code is a 3- or 4- digit number printed on the front or back of the card, and is also referred to as a security code, security validation value, CAV2, CVC2, CVV2, or CID, depending on which payment brand issued the card. * The device shows a summary of all the data that was entered during the transaction. If the operator specified a transaction amount when starting the transaction, the summary includes the total transaction amount (purchase amount plus cash back, if any). * Verify all the information is correct: * If it is correct, press the Enter button to proceed with the transaction. * If it is correct but the cardholder or operator wishes to stop the transaction, press the Cancel button to completely end the transaction. * If it is not correct, press the Cancel button to completely end the transaction, and start the transaction again from the first step.Figure 6-15 – Enter Card Number
Figure 6-16 – Enter Expiration Date
Figure 6-17 – Enter CVV/CVC/Card ID
#### How to Verify the Transaction Amount When the device is performing a transaction using the EMV Transaction Flow (as opposed to the Quick Chip Transaction Flow), devices with a display show the amount of the transaction when they prompt the cardholder to swipe, dip, or tap a card or payment device, as shown in Figure 6-18. The cardholder implicitly confirms / accepts the transaction amount by presenting payment.Figure 6-18 - Example Transaction Amount Screens
#### How to Enter PINs Devices with a touchscreen display provide support for requesting PIN from the cardholder. The device prompts the cardholder to Enter PIN (see Figure 6-19) as required by the financial institution. The device expects the PIN to be between 4 and 12 digits long. After entering the PIN, the cardholder must press the Enter button.Figure 6-19 – Enter PIN
If the double PIN entry option is enabled, the device prompts the cardholder to enter the PIN a second time (see Figure 6-20). The process for re-entry is identical to the process for the first entry.Figure 6-20 – Enter PIN Again
{% hint style="warning" %} Do not use a stylus or other hard object on the touchscreen. The touchscreen is designed for fingers only and can be scratched if misused. {% endhint %} When a device with a display prompts cardholders with PLEASE SIGN , (Figure 6-21 - Signature Capture Requested) cardholders should use the tips of their fingers to press and glide against the screen to sign, then press the OK button. To clear the current signature on the display and start over, press the Clear button.Figure 6-21 - Signature Capture Requested
Devices that do not have a touchscreen display can not prompt for or collect a signature. When these devices are aware that a signature is required after a transaction completes, they send a notification message to the host that includes the status Signature Capture Requested. In this case, the solution design collects the cardholder’s signature via a different method. --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://developer.magtek.com/hardware/card-readers/mms-dyna-devices/emv-common-kernel/dynaflex-ii-ped/documentation/user-manuals/three-way-secure-card-reader-authenticators-installation-and-operation-manual/operation.md?ask=
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