ACR1255U-J1 – Reference Manual info@acs.com.hkVersion V1.07 www.acs.com.hkPage 13 of 774.3.2. EndpointsACR1255U-J1 uses the following endpoints to communicate with the host computer:Control Endpoint For setup and control purposeBulk OUT For command to be sent from host to ACR1255U-J1(data packet size is 64 bytes)Bulk IN For response to be sent from ACR1255U-J1 to host(data packet size is 64 bytes)Interrupt IN For card status message to be sent from ACR1255U-J1 to host(data packet size is 8 bytes)