Laird BTM410 User Manual - page 16
16
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Laird Technologies
BTM410/411
Bluetooth
®
AT Data Module
REGISTER DEFAULT RANGE
COMMENT
S515
0x001F00
0.. 0xFFFFFF
Default Device Class Code to be used with AT+BTO when it is not explicitly
specified. When queried, the value is always printed as a hexadecimal number.
To change the device class of the module, after AT+BTO, use the command
AT+BTC.
S516
0x000000 0..0x2FFFFFF
Default Device Class filter to be used with AT+BTI when it is not explicitly
specified. When queried the value is always printed as a hex number.
The seventh most significant digit, can be 0,1 or 2, and is used to specify
the type of device class filter.
When 0, it specifies no filtering.
When 1, it specifies an AND mask and all 24 bits are relevant
When 2, it specifies a filter to look for devices with matching major device
class which occupies a 5 bit field from bits 8 to 12 inclusive (assuming
numbering starts at bit 0). All other 19 bits MUST be set to 0.
S517
20
2..61
Inquiry Length in units of seconds. This parameter is referenced by the
AT+BTI command
S518
8
0..255
Maximum number of responses from an inquiry request. This parameter
is reference by the AT+BTI command. If this number is set too high, then
AT+BTI will return ERROR 27. For a particular firmware revision, determine
the effective maximum value by trial and error. That is, set to a high value,
send AT+BTI and if ERROR 27 is returned, then retry with a smaller value.
This effective max value will remain unchanged for that particular
firmware build.
S519
500
100..6000
When S507>0, and in a connection, DSR can be used to change from data
to command state by deasserting the DSR line for less than the time specified
in this register. This value is rounded down to the nearest 100ms
S520
9600
1200..115200 Change to a standard baud rate. The effect is immediate and in fact the OK
will be sent at the new baud rate. Only one of the following baud rates are
accepted: 1200,2400,4800,9600,19200,28800,38400,57600,115200.
S521
See
Comment
1200..921600 Change baud rate to non-standard value. Laird Technologies’ modules support
any baud rate. The only limitation is the integer arithmetic involved, which may
adjust the applied rate slightly. If the internally computed baud rate is more
than 2% offset from the desired input value, then an ERROR will be returned
and the old baud rate will prevail. To inspect the actual baud rate, do ATS521?
S521 should only be used for non-standard baud rates. For standard baud
rates use S520.
The effect is immediate and in fact the OK will be sent at the new baud rate.
In the event that a non-standard baud rate is requested, it is entirely possible
that the host is not capable of generating such a baud rate. In this case the
device cannot be communicated with. If this happens, there is a
procedure to recover from this situation which is described in section titled
“Factory Default Mode”
S522
1
1
1 = CTS/RTS hardware handshaking enabled
S523
1
1..2
Number of Stop bits
S524
0
0..2
Parity. 0=None, 1=Odd, 2=Even
S526
3
1..3
This register specifies a 2 bit mask used to qualify how S Registers 520 to 524
are actioned.
When bit 0 is 1, the new comms parameter affects the UART immediately.
When bit 1 is 1, the new comms parameter is stored in non-volatile memory
So for example, to change comms parameters, but have them come into effect
only after subsequent power cycles, then this register should be set to 2, and
likewise to affect immediately and yet not have it persist over a power cycle,
the value should be set to 1. Must be set before the baud rate change.
S530
1000
100..15000
Reconnect delay when configured as master in pure-cable-replacement
mode. This value is rounded down to the nearest 100ms. See S Register
505 and 543 also
CONFIgURINg
THE BTM410/411