Open a cash drawer from Node.js or Electron
Most cash drawers (APG, MMF, Star, Epson) have no connection to the computer. They plug into the receipt printer's RJ11/RJ12 "DK" port, and the printer fires the solenoid when it receives a kick command. So opening the drawer means sending a few bytes to the printer.
const { Printer, profiles } = require('retail-print-kit');
const { NetTransport } = require('retail-print-kit/net');
async function openDrawer() {
const printer = new Printer(new NetTransport('192.168.1.50'), profiles['epson-tm-t88'], { initOnOpen: false });
await printer.open();
printer.cashdraw(); // pin 2, the usual wiring
await printer.close();
}USB works the same with new UsbTransport() from retail-print-kit/usb.
Pin 2 and pin 5
One printer can drive two drawers. cashdraw() or cashdraw(2) kicks the first, cashdraw(5) the second. If nothing happens on pin 2, the drawer cable may be wired for pin 5.
The right pulse for the printer
The command differs by printer family, and so does the pulse length a drawer needs. The profile takes care of it:
| Family | What is sent |
|---|---|
| Epson and ESC/POS compatibles | ESC p m t1 t2 with the profile's on/off times |
| Star Line Mode and Star raster | ESC BEL n1 n2 then BEL (drawer 1) or SUB (drawer 2) |
If a cheap drawer does not open reliably, use the generic-escpos profile (longer pulse) or kick twice: printer.cashdraw().cashdraw().
Open the drawer after printing
printer.text('Thank you').cut().cashdraw();
await printer.close();Is the drawer open?
const status = await printer.status();
console.log(status.drawerPinHigh);drawerPinHigh is the level of the drawer sensor pin. Whether high means open or closed depends on the drawer, so check once with yours.
From the command line
npx retail-print-kit drawer --net 192.168.1.50
npx retail-print-kit drawer --usb --pin 5Related: print a receipt, Electron.
Install
npm install retail-print-kitAll guides · Designer · npm · GitHub