ACR101I – Reference Manual
Version 1.01
www.acs.com.hk
Page 8 of 21
6.0. USB Interface
The ACR101 (CCID) is connected to a computer through a USB following the USB standard.
6.1. Communication Parameters
The ACR101 (CCID) is connected to a computer through USB as specified in the USB Specification.
The ACR101 (CCID) is working in high speed mode, i.e. 480 Mbps, for the flash memory.
Pin
Signal
Function
1
V
BUS
+5 V power supply for the reader
2
D-
Differential signal transmits data between ACR101 (CCID) and computer.
3
D+
Differential signal transmits data between ACR101 (CCID) and computer.
4
GND
Reference voltage level for power supply
6.2. Endpoints
The ACR101 (CCID) uses the following endpoints to communicate with the host computer:
Control Endpoint 0
For setup and control purposes
Bulk OUT Endpoint 1
For the command to be sent from host to Mass Storage Interface
(data packet size is 64 bytes)
Bulk IN Endpoint 1
For response to be sent from Mass Storage Interface to host
(data packet size is 64 bytes)
Bulk OUT Endpoint 2
For command to be sent from host to CCID Interface (data
packet size is 16 bytes)
Bulk IN Endpoint 2
For response to be sent from CCID Interface to host (data packet
size is 16 bytes)
