ACR89U-A2 – Reference Manual
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Version 1.01
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2.0. Hardware Design
2.1. Architecture
The architecture of the ACR89U-A2 library can be visualized as the following diagram:
Figure 1
: ACR89U-A2 Architecture
2.2. USB Interface
The ACR89U-A2 is connected to a computer through USB following the USB standard.
2.3. Communication Parameters
The ACR89U-A2 is connected to a computer through USB as specified in the USB Specification 2.0.,
working in full speed mode, i.e. 12 Mbps.
Pin
Signal
Function
1
V
BUS
+5 V power supply for the reader
2
D-
Differential signal transmits data between ACR89U-A2 and PC
3
D+
Differential signal transmits data between ACR89U-A2 and PC
4
GND
Reference voltage level for power supply
Table 1
: USB Interface Wiring
Note
:
In order for the ACR89U-A2 to function properly through USB interface, the device driver should
be installed.
Application
acr89.dll
acr89fnc.sys
acr89bus.sys
CCID Layer
USB
Reader
PC
PC/SC
DLL Program
Driver Program
Driver Program
Application
Program
OS
OS