I name this iot device as Laundrowallet and it's a portable iot device to check the current wallet balance from an RFID card tag for LaundromatPlus laundry system. Would be useful in cashier desk at site for quick checking user saldo balance rfid card.

It's build from Wemos D1 mini with esp12F chipset and an ssd1306 OLED display for the status display and RC522 RFID card reader as an input.

How to set up

Before using this laundrowallet iot device, it needs to be set up first. Connect this laundrowallet iot device to a power source (usually is any power bank that had an usb 5V/500mA output as it was meant to be a portable iot device).

If this is the first time to power on the device, the laundrowallet device will act as an Access Point device automatically. If not, you can push the reset button twice on the device to enter AP mode for set up.
This set up is necessary since we have to tell this laundrowallet iot device to connect to which server to get the user data.

Use any android / ios device and scan the wifi for Laundrowallet AP ssid and connect to it. After its connected, it will be redirected to captive portal and ask to sign into the network, do that and it will show the Wifi Manager page like this :

As previously stated, we need to tell which server and database we want to connect to get the user data. So, after scanning the WiFi nearby you can choose the correct network WiFi SSID for this device to connect to and also fill it in the server address and database name.
The server address and database name is specific for each outlet / branch and it depends on the infrastructure network of LaundromatPlus system.

How to use

Once it's connected to Laundromat network and its server the device is ready to use. To check the saldo balance of user RFID card is easy, just tap the card near the RDID sensor and the iot device will get the card's ID and cross checking them with the API data on the server for the current saldo balance of that card.

Wrapping Up

Made this simple little iot device as part of the Laundromat Plus system project that I working on during this past month. That's it for now …