I'm trying to read NFC Tag UID by utilizing external USB NFC Reader acr122u and WebUSB API
I'm able to authorize USB device, turn off/on buzzer, change led color etc.,
but unable to read Tag UID.
var usbd = {};
let device;
let deviceEndpoint = 0x02;
let powerUpDevice = new Uint8Array([0x62,0x00, 0x00, 0x00, 0x00,0x00,0x00,0x01,0x00, 0x00]).buffer;
let getCardUID = new Uint8Array([0xff,0xca,0x00,0x00,0x04]).buffer;
(function() {
'use strict';
usbd.authorize = function(){
navigator.usb.requestDevice({ filters: [{ vendorId: 0x072f }] })
.then(selectedDevice => {
device = selectedDevice;
console.log(device.configuration.interfaces[0].interfaceNumber);
console.log(device.manufacturerName);
console.log(device.productName);
console.log(device);
return device.open()
.then(() => {
if (device.configuration === null) {
return device.selectConfiguration(1);
}
});
})
.then(() => device.claimInterface(0))
.then(() => device.transferOut(deviceEndpoint, powerUpDevice)
.then(transferResult => {
console.log(transferResult);
}, error => {
console.log(error);
device.close();
})
.catch(error => {
console.log(error);
})
);
};
usbd.getDevice = function(){
return navigator.usb.getDevices().then(devices => {
return devices.map(device => new usbd.device(device));
});
};
usbd.device = function(device) {
this.device_ = device;
};
usbd.getTagUID = function(){
device = this.getDevice();
device
.then(device => {
device[0].device_.open()
.then(() => device[0].device_.claimInterface(0))
.then(() => device[0].device_.transferOut(deviceEndpoint, getCardUID)
.then(transferResult => {
console.log(transferResult);
}, error => {
console.log(error);
device[0].device_.close();
})
.catch(error => {
console.log(error);
})
)
.then(() => device[0].device_.claimInterface(0))
.then(() => device[0].device_.transferIn(deviceEndpoint, 16)
.then(USBInTransferResult => {
if (USBInTransferResult.data) {
console.log(USBInTransferResult.data.getUint32(0));
}
}, error => {
console.log(error);
device[0].device_.close();
})
.catch(error => {
console.log(error);
})
);
});
};
$('#connect').click(function(){
usbd.authorize();
});
$('#readCard').click(function(){
usbd.getTagUID();
});
})();Another question is how to detect a tag when it's in range of NFC reader, i.e. not to detect it only once, but detect every tag placed/removed on the reader.
Thank You!