In BioStar 1 you can create an anti-passback zone if you have purchased and applied a Standard Edition license. 

Refer to the attacked Administrator's manual regarding the configuration. 

If you only need to configure anti-passback between two devices connected with RS485

Refer to the steps below to configure a door based anti-passback. You need the license for this as well. 

1. Add a device to BioStar with ethernet connection. 

2. Set the RS485 Mode to Host.

3. Set another device RS485 setting to Slave.
** You have 3 options to configure a device: 

 a. device with LCD: configure on the device menu. Refer to the device manual. 

 b. Configure device settings with BioStar Config with a ethernet connection on the local network 

 c. Configure device settings after connecting the device to BioStar with ethernet

4. Right click on the host device and click Add Device(Serial)

5. Click Next to search by Serial. 

6. Click Next and add the device. 

7. Click Finish

The slave device will appear below the host device. 

8. Go to the Doors menu.

9. Click Add New Door

10. Right click on the door and click Add Device

11. Select the host device and click OK.

12. Right click on the door again and click Add Device

13. Choose the slave device and click OK.

Now 2 devices should be under one door

14. Click on the Anti-passback checkbox.

15. Configure your APB type.

- Soft: APB violation log will be recorded but the user will be allowed access. 

- Hard: APB violation log will be recorded and the user will not be allowed to access. 

16. Configure your Reset Time.

- This resets the antipassback violation after the specified minutes. 

- If you set it to 0, it will never be reset. The admin will have to manually reset it in the Monitoring menu. 

17. Click Apply