ACR3901U-S1 – Reference Manual
Version 1.09
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Page 11 of 96
5.3.2. Endpoints
ACR3901U-S1 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 ACR3901U-S1
(data packet size is 64 bytes)
Bulk IN
For response to be sent from ACR3901U-S1 to host
(data packet size is 64 bytes)
Interrupt IN
For card status message to be sent from ACR3901U-S1 to host
(data packet size is 8 bytes)
5.4. User Interface
5.4.1. Mode Selection Switch
ACR3901U-S1 has three modes: USB, Off, and Bluetooth. User can select one mode at a time as a
data transmission interface.
Symbol
Switch
Active Mode
USB
PC-linked
Off
No power
Bluetooth
Bluetooth
Table 4
: Mode Selection Switch