Printers our shops run: how StoreDesk reaches a receipt printer, and what has been tested

Two roll widths

• 58 mm (2-inch) rolls print 32 characters a line, or 42 in small text.
• 80 mm (3-inch) rolls print 48 characters a line, or 64 in small text.

A preview shows exactly what will print before anything goes to the printer. Receipts always print in English, because receipt printers carry no Indian-language script. Any printer can also print the bill as an A4 or A5 PDF.

The ways to reach the printer

You choose how the printer is connected, on the Receipt roll, and the next receipt starts on the way that worked last time:

• USB cable — in Chrome or Edge on a computer.
• Bluetooth — in Chrome or Edge, on a computer or an Android phone. On a computer, pair the printer in Windows or macOS settings first.
• A printer paired as a COM port — in Chrome or Edge on a computer; the usual way for a Bluetooth printer that Windows pairs as a serial port.
• The printer’s own driver — through the print dialog, in any browser on a device where the printer is installed. StoreDesk sends the receipt as a sharp black-and-white picture of the roll, so the type prints solid.
• The RawBT app, on Android — a free app that passes the receipt to a Bluetooth printer a web page cannot reach. Its free version adds a small watermark.

On Windows

For a Bluetooth printer, pair it in Settings → Bluetooth & devices (the PIN is usually 0000 or 1234). Then choose Paired printer / COM port and pick the port named “Standard Serial over Bluetooth link (COM…)”. If nothing prints, try the other COM port of the pair.

For a USB printer that does not appear in the USB list, install the maker’s Windows driver and choose The printer’s own driver.

On an Android phone

In Chrome, choose Bluetooth: your printer appears in the list if it speaks Bluetooth Low Energy. If it is not in the list, install RawBT from the Play Store, add the printer in RawBT, and choose RawBT app (Android) in StoreDesk.

On an iPhone or iPad

Safari has no USB, Bluetooth or COM-port printing, so those ways do not appear there. The printer’s own driver works only where the device can print to the printer. A receipt printer with an iPhone or iPad has not been tested; print the A4 or A5 PDF, or send the bill’s link on WhatsApp.

The UPI QR on the roll

When your shop has a UPI ID, the receipt carries a scan-to-pay QR. Each square of the code is printed 5 printer dots wide — 0.625 mm — so the code is about 23 mm across for a short shop name and about 31 mm for a long one, on both roll widths. A code too wide for the roll steps down to 4 dots, and if it still does not fit, StoreDesk prints no code at all rather than one a phone cannot read; the Pay by UPI line stays.

The size was checked by decoding a simulated print of the roll. Scanning a real printed roll with a phone has not been tested yet.

What has been tested, and what has not

Printed on a real receipt printer so far: the printer’s own driver, on a 58 mm USB printer under Windows. That is where the solid type and the bigger QR came from.

Not yet run on a real printer: the USB cable, Bluetooth, COM-port and RawBT ways. They are built and checked against a simulated printer, and they stay a beta until they have printed on real ones.