User's Manual

Enhanced Class 1 Bluetooth v2.1 Module
User’s Guide
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CONN-GUIDE-BT740_v0.2
<Guard time><Esc Chr><Guard time><Esc Chr><Guard time><Esc Chr><Guard time>
Where <Guard time> is 100 milliseconds.
The four guard time means that even when a file transfer is occurring and it happens to be full of <Esc
Chr> characters, it is not going to drop into command mode. This is because when transferring a file, it
happens as fast as possible and so the inter character gap will be significantly shorter than the <Guard
time>.
The <Esc Chr> character can be changed via the S2 register.
14.2 Profiles
This section describes all the profiles that the module is capable of making and accepting connection
when in AT mode.
14.3 Serial Port Profile (SPP)
UUID : 1101
You must set S Register 9003 bit 0 to make this profile active.
Outgoing connections are initiated using the command: “ATD<bd_addr>”
Incoming connections result in at least one “RING <bd_addr>” response to the host. If S Register 0 is a
non-zero value then after the appropriate number of RING responses the connection automatically
accepts and a “CONNECT <bd_addr>,1101,<” response sends to the host. If S Register 0 is 0, then the
incoming connection accepts by the host using the command ATA or rejected using ATH.
On connection, depending on the value of S Register 531, the module enters pass through mode (data
transparently exchanged between UART and air-side) or in command+online mode. In the latter, data
sends to the peer using the “ATX<string>” command and any data from the peer either dumps silently
(S531=1) or send to the host in an “RX<string>” asynchronous response (S531>1).
When in pass-through mode, the escape sequence ^^^ puts the module into command and online mode
so that a disconnection can initiate. A disconnection can also initiate by deasserting the DSR input line of
the module for more than 500 milliseconds.
On disconnection a “NO CARRIER” async response sends to the host.
14.4 HID Device Profile (HID)
UUID : 1124
S Register 9003 bit 1 must be set to make this profile active. In addition, S register 9039 must be set to 0
and above to enable a DEVICE HID profile and a negative value to enable a HOST HID profile.
Outgoing connections initiate using the command: “ATD<bd_addr>,1124”
Incoming connections are automatically accepted and a “CONNECT <bd_addr>,1124,<” sends to the
host.
With the HID profile, a built-in standard keyboard HID descriptor is supplied along with a canned mode of
operation. It enables a legacy device generating ASCII characters to present to a host as a compliant HID
keyboard.
In canned mode, each ASCII character (ASCII characters 128 and above are silently discarded) results in
two INPUT reports to the host. The first is a corresponding key press and the second is a corresponding
key unpress. When the host sends the 1 byte OUTPUT report sends to the host as-is.