I have scanner of make Datalogic Magellan 1500i. When I connect it to my machine via USB, I can use the following command to see what barcodes the scanner reads:
cat -v /dev/ttyACM0
F4009900511513^M
When we receive these scanners, we want to configure them for our purposes. This process is done by scanning barcodes provided in the manual of the scanner.
I want to do this programmatically, by sending the value of the barcodes to the scanner directly, simulating that they have been scanned. I've read some questions here and found some suggestions, but I cannot getthe scanner to react to my events.
I run the command above in one terminal, and in another I echo to the same tty device:
echo "test" > /dev/ttyACM0
However there is nothing displayed in the terminal reading the output, and the scanner shows no signs of receiving what I send.
This is what I get from lsusb -D /dev/bus/usb/001/039
Device: ID 05f9:4002 PSC Scanning, Inc.
Device Descriptor:
bLength 18
bDescriptorType 1
bcdUSB 2.00
bDeviceClass 2 Communications
bDeviceSubClass 0
bDeviceProtocol 0
bMaxPacketSize0 64
idVendor 0x05f9 PSC Scanning, Inc.
idProduct 0x4002
bcdDevice 0.49
iManufacturer 1
iProduct 2
iSerial 3
bNumConfigurations 1
Configuration Descriptor:
bLength 9
bDescriptorType 2
wTotalLength 67
bNumInterfaces 2
bConfigurationValue 1
iConfiguration 0
bmAttributes 0x80
(Bus Powered)
MaxPower 500mA
Interface Descriptor:
bLength 9
bDescriptorType 4
bInterfaceNumber 0
bAlternateSetting 0
bNumEndpoints 1
bInterfaceClass 2 Communications
bInterfaceSubClass 2 Abstract (modem)
bInterfaceProtocol 1 AT-commands (v.25ter)
iInterface 4
CDC Header:
bcdCDC 1.10
CDC ACM:
bmCapabilities 0x07
sends break
line coding and serial state
get/set/clear comm features
CDC Union:
bMasterInterface 0
bSlaveInterface 1
CDC Call Management:
bmCapabilities 0x01
call management
bDataInterface 0
Endpoint Descriptor:
bLength 7
bDescriptorType 5
bEndpointAddress 0x83 EP 3 IN
bmAttributes 3
Transfer Type Interrupt
Synch Type None
Usage Type Data
wMaxPacketSize 0x0010 1x 16 bytes
bInterval 1
Interface Descriptor:
bLength 9
bDescriptorType 4
bInterfaceNumber 1
bAlternateSetting 0
bNumEndpoints 2
bInterfaceClass 10 CDC Data
bInterfaceSubClass 0 Unused
bInterfaceProtocol 0
iInterface 5
Endpoint Descriptor:
bLength 7
bDescriptorType 5
bEndpointAddress 0x81 EP 1 IN
bmAttributes 2
Transfer Type Bulk
Synch Type None
Usage Type Data
wMaxPacketSize 0x0040 1x 64 bytes
bInterval 0
Endpoint Descriptor:
bLength 7
bDescriptorType 5
bEndpointAddress 0x02 EP 2 OUT
bmAttributes 2
Transfer Type Bulk
Synch Type None
Usage Type Data
wMaxPacketSize 0x0040 1x 64 bytes
bInterval 0
This is what I see in journalctl when I unplug the device and plug it back in again:
kernel: usb 1-8: USB disconnect, device number 39
upowerd[1029]: unhandled action 'unbind' on /sys/devices/pci0000:00/0000:00:14.0/usb1/1-8/1-8:1.1
upowerd[1029]: unhandled action 'unbind' on /sys/devices/pci0000:00/0000:00:14.0/usb1/1-8/1-8:1.0
upowerd[1029]: unhandled action 'unbind' on /sys/devices/pci0000:00/0000:00:14.0/usb1/1-8
kernel: usb 1-8: new full-speed USB device number 40 using xhci_hcd
kernel: usb 1-8: New USB device found, idVendor=05f9, idProduct=4002, bcdDevice= 0.49
kernel: usb 1-8: New USB device strings: Mfr=1, Product=2, SerialNumber=3
kernel: usb 1-8: Product: Point of Sale Handable Barcode Scanner
kernel: usb 1-8: Manufacturer: Datalogic USA Inc.
kernel: usb 1-8: SerialNumber: E19I43871
kernel: cdc_acm 1-8:1.0: ttyACM0: USB ACM device
mtp-probe[7447]: checking bus 1, device 40: "/sys/devices/pci0000:00/0000:00:14.0/usb1/1-8"
mtp-probe[7447]: bus: 1, device: 40 was not an MTP device
snapd[748]: hotplug.go:199: hotplug device add event ignored, enable experimental.hotplug
upowerd[1029]: unhandled action 'bind' on /sys/devices/pci0000:00/0000:00:14.0/usb1/1-8/1-8:1.1
upowerd[1029]: unhandled action 'bind' on /sys/devices/pci0000:00/0000:00:14.0/usb1/1-8/1-8:1.0
upowerd[1029]: unhandled action 'bind' on /sys/devices/pci0000:00/0000:00:14.0/usb1/1-8
Is there any way to achieve what I'm trying to do? Am I looking in the wrong place?
Additional information update
Checking the options used for the tty yields this result:
$ stty -F /dev/ttyACM0
speed 115200 baud; line = 0;
eof = ^A; min = 1; time = 0;
-brkint -icrnl -imaxbel
-opost -onlcr
-isig -icanon -iexten -echo -echoe -echok -echoctl -echoke
When scanning the barcode the code ends with ^M, and searching for that leads to additional answers. I'm thinking it's perhaps related to me not sending a correct line ending when echoing to the device, but I can't figure out how to change the accepted line ending or how to send the correct line ending.
Further debugging
Tried setting eol, eof and enabling icrnl:
stty eol 'x' eof 'x' -F /dev/ttyACM0 115200 -brkint icrnl -imaxbel -opost -onlcr -isig -icanon -iexten -echo -echoe -echok -echoctl -echoke
The latter now prints a new row for each code scanned:
$ cat -v /dev/ttyACM0
F4009900511513
F4009900511513
F4009900511513
Tried sending correct data with printf after suggestion, no result in the terminal reading the device:
printf 'F4009900511513\r' > /dev/ttyACM0
printf 'F4009900511513\r\n' > /dev/ttyACM0
Final solution
I emailed Datalogic and the following seems to work:
printf 'F400990051153\x0d' > /dev/ttyACM0
This results in the terminal reading to output the following:
$ cat -v /dev/ttyACM0
^F
printf 'test\r\n'will add carriage-return (^M) and newline (^J). (To check, pipe the printf into|od -c).