5 Hardware lock to disable USB mass storage device
You can lock the VTAP50 so that its firmware and configuration cannot be changed. You can
either do this in software, or simply disable the mass storage device in hardware.
A software lock prevents changes but leaves some files visible. A hardware lock means that
the VTAP50 will no longer be detected as a USB mass storage device. (It will still behave as an
HID keyboard device and, if enabled, the virtual COM port will behave as a composite USB
device consisting of HID keyboard and USB virtual COM port.)
You can use a hardware lock provided the jumper labelled LOCK (close to the
MicroUSB connector) remains accessible on a VTAP50 OEM module.
Note:
On VTAP50 OEM modules, although the contact is present, connector pins and
jumpers will need to be supplied.
Connect a jumper across LOCK on the PCB to lock the device, preventing firmware or
configuration changes via the mass storage device. (It may still be possible to update the
firmware or configuration via the command interfaces of the virtual COM port or serial ports,
if they are enabled.)
Figure 5-1 Jumper positions on VTAP50 PCB v1 hardware
When you start the VTAP50, the presence of this jumper means the connected PC will not
detect a USB mass storage device. The VTAP50 will only be detected by the PC as a keyboard
(or keyboard and virtual COM port).
At any time you can remove the jumper across LOCK. When you restart the VTAP50, it will
be detected as a USB mass storage device and you will be able to make firmware or
configuration changes again.
VTAP50 OEM MODULE INSTALLATION GUIDE
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