ACR3901T-W1 – Reference Manual
Version 1.02
www.acs.com.hk
Page 14 of 100
6.1.2.
Profile Selection
The ACR3901T-W1 is a smart card reader that is designed to use Bluetooth technology as an
interface to transmit data. A customized service called Commands Communication with three pipes is
used: one pipe is used for command request, the second pipe is for command response, and the third
pipe is used to notify the paired device about the card and sleep mode status.
Also, the current reader’s battery status is significant when the reader is operating in Bluetooth mode,
hence, a customized battery service is used to notify the paired device about the current battery
status. When there is a change in the battery status, the reader will notify the paired device through a
specific pipe. To simplify, the battery levels are divided into three groups. Below is a table
summarizing the battery level and its corresponding return value:
Status
Voltage
Return Value
Sufficient battery
≥ 3.3 V
FEh
Low battery
<3.3
V and ≥ 2.9 V
Value other than FFh/FEh/00h
No battery
<2.9 V
00h
USB mode
FFh
In Card Status Notification service, it will notify the paired device of any changes in the card status or
when the reader enters sleep mode. Below is a list of the status and the corresponding return value:
Status
Return Value
No card present
50 02h
Card present
50 03h
Reader has entered sleep mode
50 04h
Finally, to provide more reader information to the user, a customized Device Information service was
added. This can only be read manually, or by an application request. The characteristics include
Manufacturer Name
,
Firmware Revision
,
Model Number
, and
Serial Number
.
Figure 3
: nRFgo Studio GATT Setting Interface
