Retail POS Hardware Checklist
A POS application and a device being individually supported does not prove they work together. Test the exact computer, operating system, connection method, driver, paper size, and workflow that will be used at the counter.
Record the exact setup
| Device | What to record | Minimum workflow test |
|---|---|---|
| Receipt printer | Model, USB/network/Bluetooth connection, driver, paper width, and cutter support. | Print a sale, return, duplicate receipt, long item list, tax lines, and non-ASCII customer text. |
| Barcode scanner | Model, keyboard or serial mode, suffix settings, and barcode types. | Scan known, unknown, repeated, weighted, and damaged labels without adding the wrong item. |
| Cash drawer | Drawer model, printer kick-port wiring, and pulse settings. | Open only for authorized payment and manual-open actions; confirm failed prints do not create unsafe behavior. |
| Weighing scale | Model, protocol, port, baud rate, units, decimal precision, and calibration status. | Read stable, changing, zero, and out-of-range weights and verify the billed quantity. |
| Customer display | Display type, resolution, orientation, cable, and browser or serial mode. | Show item, quantity, discount, tax, total, payment, and cleared-sale states without exposing another customer. |
| Payment terminal | Provider, terminal model, integration method, network dependency, and settlement process. | Test approved, declined, cancelled, timed-out, reversed, and duplicated-payment paths. |
Test the failures, not only the happy path
- Disconnect the internet and verify every workflow advertised as Offline POS behavior.
- Restart the computer with devices unplugged, then reconnect them in a different order.
- Run a full shift-length test with realistic receipt volume and scanner use.
- Verify that a failed peripheral does not block cash billing or corrupt an in-progress sale.
- Restore a backup onto separate test hardware and reconcile totals before rollout.
Keep an evidence record
Record the test date, software version, package filename and checksum, operating-system build, device identifiers, driver versions, workflows attempted, failures, and workarounds. “USB printer supported” is too broad to reproduce or trust.
Posnic is offline-first open source POS and Billing Software for retail shops and restaurants. Its public Posnic/POS source repository includes a versioned hardware matrix that separates implemented interfaces from device-specific evidence, so an Online/Offline POS rollout can be evaluated without turning a source connector into a hardware certification.