Chapter 2 - Faqs - Hand Held Products 3800i Application Note

2
FAQs
Q: Can I plug the Adaptus Imaging Technology device into any USB port?
A: Adaptus Imaging Technology devices are high powered, therefore you can't use the ports of bus-powered HUBs. All other
ports are fine.
Note: Usually a hub comes with a power supply, and switches automatically to a self-powered hub when the power supply is
connected.
Q: Can I extend the length of the USB cable?
A: No, USB is a high speed system and the cable length is critical. The maximum length cable is 16.5 feet (5 meters).
Q: Can I use more that one Adaptus Imaging Technology device in one system?
A: Yes, several scanners are no problem for PCs and Macs. Each has its own unique serial number, so you can distinguish
the devices. IBM SurePOS cash registers only accept a single scanner per type. There are two types: hand held and
tabletop.
Q: Can I configure Adaptus Imaging Technology devices via USB?
A: This depends on the interface you selected. COM port emulation can be used to send data to the Adaptus Imaging
Technology device, then Visual Menu can be used to configure the scanner. The HID POS interface can also be used from
your application.
Q: Can I upgrade the firmware via the USB?
A: Yes.
Q: I can't send any HID report to the device with WriteFile.
A: Output reports must be the maximum size for Windows' HID. Every output report must be padded up to that maximum size.
The structure HIDP_CAPS contains the member OutputReportByteLength, which is used to pad your report buffer.
Note: Only the true size of a report goes through the wire.
Newer SDKs for Windows 2000/XP contain a function called WriteReport, but it is not supported by the Windows 9x family.
Q: I used a special filter driver with Windows 98 to get details about the keyboard (bar code reader). But it does not
work with Windows 2000 (XP).
A: This is a feature of these operating systems. For security reasons, they open all keyboards and pointing devices for
exclusive access.
Q: What is the difference between the HID POS with the keyboard interface and the pure HID POS?
A: The USB interface index is different (1 for the HID POS with the keyboard, 0 for pure HID POS). All output is sent to the
keyboard by default, however, you can redirect the output to the HID POS.
Pure HID POS can send 64 bytes every 4 mSec. The composite version only sends 64 bytes every 8 mSec. This is a
compromise between speed and overhead on the USB. If this was changed to 64 bytes every mSec, it would result in more
load on the USB.
Q: Why is there another HID POS interface with the keyboard?
A: The main purpose for this interface is to allow the device to be triggered, while still using keyboard emulation for outputting
data. This interface can also be used for a firmware upgrade.
Q: My application program can't access COM ports above 4.
A: You can try to change the COM ports so you get the Adaptus Imaging Technology devices under this limit. You can change
the COM port assignment with the device manager. Go to port, then right click on the port you want to change, select
properties, and click on advanced.
Q: My application program does not show COM ports above 15.
A: It uses a Windows API function (EnumPorts) that has this limitation.
Q: My device is not recognized by the PC on a USB2 port, or I get blue screens, or Windows crashes when I unplug
the device.
A: This is a PC driver issue. Some older drivers for the NEC chip have a bug, possibly rev 2.01 of ousbehci.sys and
ousb2hub.sys. Upgrade to a newer revision, or use the Microsoft driver for USB2.
USB Interfaces User's Guide 2 - 1