ACR3801 – Reference Manual
Version 2.01
www.acs.com.hk
Page 9 of 62
6.0. USB Interface
6.1. Communication Parameters
ACR3801 is connected to a computer through USB as specified in the USB Specification 2.0.
ACR3801 is working in full speed more, i.e. 12 Mbps.
Pin
Signal
Function
1
VBUS
+5 V power supply for the reader
2
D-
Differential signal transmits data between ACR3801 and PC
3
D+
Differential signal transmits data between ACR3801 and PC
4
GND
Reference voltage level for power supply
Table 2
: USB Interface Wiring
Note:
In order for the ACR3801 to function properly through USB interface, either ACS proprietary
device driver or the ACS PC/SC device driver has to be installed.
6.2. Endpoints
ACR3801 uses the following endpoints to communicate with the host computer:
Control Endpoint
For setup and control purpose
Bulk OUT
For command to be sent from host to ACR3801
(data packet size is 64 bytes)
Bulk IN
For response to be sent from ACR3801 to host
(data packet size is 64 bytes)
Interrupt IN
For card status message to sent from ACR3801 to host
(data packet size is 8 bytes)