The serialPOS Driver

This section talks about using LCDproc with a point of sale ("POS") character-display.

The serialPOS driver is currently working with the AEDEX emulation protocol, but can be extended to work with various other protocols.

The driver should operate most character POS displays with a serial (RS-232) input. Because these displays use a standardized protocol, if the protocol is supported by your display, it should work as expected. Feedback is welcome.

Table 5.17. serialPOS: Emulation Protocol Status

ProtocolDisplay testedCurrently SupportedRemark
AEDEXEmaxYes
IEE No
Epson No
Emax No
IBM No
Logic Controls No
Ultimate No


(): Feature not tested.

Connecting The Display

Connecting the display should consist of simply plugging it into your computer's RS-232 port. Because these displays typically support full RS-232, no additional wiring is needed. If your computer does not have such a port (many newer computers don't), you can use a USB to serial adapter with the appropriate driver.

Note

If your display supports a pass-through function, but you do not have another RS-232 device connected to the pass-through port, you may experience hangs if an improperly formatted command sneaks through. This is because the display is waiting for the pass-through device to accept the data and a blocking state is created within the device. You can either connect another RS-232 device, or rewire the display to send the pass-through commands back to your computer.

Configuration in LCDd.conf

[serialPOS]

Device= DEVICE

Device to use in serial mode. Usual values are /dev/ttyS0 or /dev/cu.usbserial. Default is /dev/lcd.

Size= WIDTH x HEIGHT

Specifies the size of the VFD in characters. If not given, it defaults to 16x2.

Type= { IEE | AEDEX | Epson | Emax | IBM | LogicControls | Ultimate }

Set the communication protocol to use with the POS display. If not specified it defaults to AEDEX. Currently, only AEDEX is supported.

Speed= { 1200 | 2400 | 9600 | 19200 | 115200 }

Set the the baud rate communication with the POS display. If not given the default of 9600 is used.