Wiegand 26-bit and 34-bit, and which mode to set.
The eight reader bit modes, the reader models they belong to, and the two mistakes that turn into call-outs. Written for the person at the panel with a card that will not read.
Why the format has to be set
A Wiegand reader sends the card's data as a stream of bits. The controller has to be told how to slice that stream into a card number.
Set the wrong mode and the card either reads as a different number or does not read at all. The format belongs to the reader and the card — not to the door — so two doors on one system can legitimately need two different modes.
Reader modes 01 to 08
The modes available in the RFID reader bit configuration screen, and what each one reads.
| Mode | Format | What the controller reads |
|---|---|---|
01 | Wiegand 26-bit (without facility code) | Last 5 digits of the EM card number |
02 | Wiegand 26-bit (with facility code) | First 8 digits, facility code included |
03 | Wiegand 34-bit (with facility code) | 34-bit format with facility code |
04 | Wiegand 34-bit (without facility code) | 34-bit format without facility code |
05 | Wiegand 42-bit (without facility code) | Extended format, card number only |
06 | Wiegand 34-bit, 5-digit card number | 5-digit card numbers |
07 | Wiegand 32-bit, 5-digit card number | 32-bit format with 5-digit card numbers |
08 | Wiegand 34-bit, 10-digit card number | Full 10-digit card number |
Modes and wording as listed in the VAULT Site reader bit configuration reference. The mode selected must match the format the reader and the RFID card use — a mismatch shows up as card reading errors or no read at all.
Which reader takes which mode
| Reader | Format it uses | Controller mode |
|---|---|---|
ID W26 | Wiegand 26-bit | Mode 1 (EM format) |
IC W34 | Wiegand 34-bit | Mode 3 (MIFARE format) |
AY-701 / AY-800 | 26-bit or 34-bit, selected by the brown wire | The mode matching the card in use |
AY-K150 keypad | 4-bit keypad format, for PIN or card plus PIN | Keypad mode |
On the AY-701 and AY-800, EM mode leaves the brown wire unconnected; connecting the brown wire enables MIFARE. Confirm the exact reader type on the sticker on the back of the reader cover before setting the mode.
Setting the mode on a controller
- 01
Open the reader bit configuration
Control Panel then Tool & Settings, then RFID Reader Bit Configuration.
- 02
Select the mode for that reader
Take the mode from the table above, using the reader model and the card type at that door. Record it against the door, not against the site.
- 03
Program the reader bits
Program Reader Bits writes the setting to the controller. Do this before presenting a test card, so a failed read means wiring rather than a setting you have not applied yet.
- 04
Confirm with a card at the door
Present a known credential and check that the number in the event log is the card's real number. A number that is close but not equal is a mode mismatch, not a damaged card.
When a card reads as the wrong number
Two modes read different slices of the same card, so the same credential can arrive at the controller as two different numbers across two doors. When that happens, compare the reader models and the modes set for each port before blaming the card or the reader.
A card that reads at one door and not another usually points at the mode or the data wiring on the door that fails — work the reader fault-finding order before replacing hardware.
The bit-format reference
The mode table, the reader-to-mode mapping, the keypad setting and the programming steps on one printable sheet — the page you keep in the site folder.
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.
VAULT Site support documentation — RFID reader bit configuration: modes 01 to 08, EM and MIFARE examples, and the AY-K150 keypad reader.
VAULT Site support documentation — reader in/out fault-finding: reader models ID W26 and IC W34, the AY-701 and AY-800 brown wire, and the mode each requires.
Falco S32, CF PoE and ZG IP controller datasheets — standard Wiegand 26/34 reader format.