VHL without reader configuration
This mode covers the same use case as the standard VHL implementation. However, the following restrictions apply:
- You cannot format cards.
- You cannot work with complex card structures, e.g. where the data you want to access is distributed across multiple files or blocks.
We only recommend this mode if:
- You don't want to configure the readers.
- You don't want to specify the card structure (i.e. the parameters to access the card) before putting readers in operation, but control the parameters flexibly during reader operation.
What is VHL?
VHL stands for Very High Level card access. It's a set of simplistic, card-type-independent commands (learn more).
How it works
This approach is similar to the standard VHL implementation. The only difference: You don't configure readers in advance. Instead, you configure them temporarily at runtime via the host.
Exceptional cases requiring a configuration
In the vast majority of cases, you won't need to configure the reader. A configuration is only necessary if one or both of the following apply:
- USB HID (recommended with the SDK)
- USB virtual COM port (recommended when not using the SDK, required for RDP)
Ethernet (client only)
For Ethernet server implementations, please use VHL & Autoread.
Set up SDK
The easiest way to use VHL is the BALTECH SDK, available for Windows, macOS, and Linux.
Alternative for unsupported platforms
To set up the SDK:
- Downloadcall_made the SDK from our website.
- Get familiar with its components. We recommend you get started by trying out the app notes.
- Integrate the SDK into your application.
- Set up a protocol stack to be able to run commands.
Run VHL.Selectcall_made to scan for cards.
Set AcceptConfCard = false
Readers without a preinstalled configuration are vulnerable to attacks with tampered ConfigCards. To prevent this, set the parameter AcceptConfCard = false, so readers will ignore any ConfigCard presented to them.
With this command you dynamically create a "VHL file". This is a description of the card's data structure. It's needed to configure the reader for subsequent commands.
Run the VHL command(s)call_made required for your operations. Here are the most important ones:
Reader hardware control
There are various commands to control the reader hardware. You can control reader feedback (e.g. LED and beeper), reboot the reader, check its firmware version, etc.
That's it for the development part. You can now install the readers (and, if necessary, deploy the configuration) as described here.
Troubleshooting & support
Got stuck somewhere along the way? Don't worry, we'll help you troubleshoot: