Wiegand to OSDP, door by door.
What changes when a reader interface moves to OSDP — and what stays where it is. Written for the installer holding the conversion scope, not for a brochure.
The data path changes. The door does not.
Wiegand sends card data as two pulse trains over a pair of data lines, D0 and D1. OSDP carries the same card number over a serial pair, and adds a return path so the controller and the reader can report status to each other.
The change happens at the reader port. The lock, the door contact, the exit button, the break glass and the credentials all stay exactly as they are.
What you cannot do is change one end only. Wiegand and OSDP are different interfaces, so the controller has to support the interface the reader is going to use.
Which Falco controllers can drive an OSDP reader
| Controller | Reader interface | OSDP |
|---|---|---|
S32 IP Controller | Wiegand 26/34 format standard | OSDP v2, optional |
CF PoE Controller | Wiegand 26/34 format standard | OSDP v2, optional |
ZG IP Controller | Wiegand 26/34 format only | Not supported |
OSDP v2 is an optional item on the S32 and CF PoE lines, so confirm it on the units you are converting. A site running ZG controllers needs a controller change before any reader can move to OSDP — that series carries Wiegand 26/34 only.
Before you cut over
Work through these in order. Each one is a reason a conversion stalls halfway through the door list.
- 01
Inventory the readers
Record each reader's model, its read format, and the bit mode the controller is currently set to. The reader model decides the mode, not the card.
- 02
Confirm OSDP on the controller
Check the controller line and the option fitted to the unit. S32 and CF PoE can carry OSDP v2; ZG cannot.
- 03
Check the cable
Wiegand uses four conductors — 12V, 0V, D0 and D1. OSDP needs its serial pair plus power. The fault pattern is the same either way: a run that shares a tray with mains cable reads intermittently, so use screened cable and keep the reader run clear of power.
- 04
Leave the lock wiring alone
The lock, door contact, exit button and break glass land on the controller's inputs and relay, not on the reader. A reader swap does not touch them.
- 05
Commission one door first
Convert a single door, present a test credential at that door, and confirm the read in the controller event log before starting the next reader.
- 06
Record what you removed
Write down the bit mode and the wiring of the reader you take off. If a reader has to go back on, that record is the whole rollback plan.
What OSDP does not change
Card numbers. The same credential is read; what changes is how the bits reach the controller.
The bit format. The controller still has to be set to the format the reader and the card use.
The controllers that do not support it. A ZG site converts by changing controllers, not by changing readers.
Egress. The fire release, break glass and exit button paths do not depend on the reader interface.
The migration checklist
One sheet you can print and carry to site: reader inventory, controller and option check, cable check, and per-door commissioning sign-off.
No form. Download it, use it on site, and send the project our way when you want the model list priced.
Where this comes from.
Every technical statement on this page is drawn from Falco documentation. Nothing here is written to fill a page.
Falco S32, CF PoE and ZG IP controller datasheets — Wiegand 26/34 format standard, OSDP v2 optional, fire alarm release on the controller.
VAULT Site support documentation — RFID reader bit configuration, including reader modes 01 to 08.
VAULT Site support documentation — reader in/out fault-finding, including screened cable and separation from mains cable.
Falco controller wiring diagrams — reader port terminals (12V, 0V, D0, D1, LED, buzzer).