Laird BTM410, User Manual

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BTM410/411
Bluetooth
®
AT Data Module
38 www.lairdtech.com Laird Technologies
AT COMMAND SET
REFERENCE
Hardware Units (BTM410 / 411)
This section covers S-Registers and AT-Commands that are related to hardware units of a BTM410 or
BTM411 device. For this section, please also refer to the bluecore data sheet [5] for further information.
1. Codec Gain
The BTM410/411 can operate with an external PCM codec. Laird provides a number of different
codec evaluation boards designed for use with the BTM410/411 development kit. For example the
ACC-05 is a codec evaluation board based around the Winbond W681360 codec [6]. The platform
provides flexible support for different codec formats (μ-law, A-law and 13 bit linear). If 13 bit linear
format is chosen, then the 13 bit sample will be transmitted over the PCM interface as the MS 13
bits of a 16 bit word. The LS 3 bits may be used to control the output gain of the codec (for example
on the Winbond W681360) and the AT software allows this output gain setting to be controlled
using s-register 589 as described in Table 3-18.
2. Hardware Units - S Registers
Table 3-18 below gives an overview on S Registers for hardware units except GPIO. For GPIO
Registers please refer to Table 3-19.
Table 3-18: S Registers for Hardware Units
Register Default Range Description
S589 8 0..8 External codec output gain
3. GPIO
On a BTM410/411 device a number of digital I/Os can be used for general purposes. Each GPIO will
be assigned to an S-Register (S651 to S663) which will be capable of both GPIO configuration (config
mode) as well as single pin read/write access (r/w mode). The bitmask of the I/O pin for direct
read/write access will be 0x01. All configuration flags are allocated to higher value bits. A bitmask
for the I/O pin will be applied to if S-Register 650 is set to 1. This will enable the user to access a
GPIO-Pin directly by reading/writing 0 or 1. If the GPIO shall be configured, S650 must be set to 0 in
order to obtain access to the GPIO configuration flags.
All logical GPIO lines can be read/written in one atomic step by new S-Register 670 at any time.
Some GPIOs can have an alternative function assigned. If the alternative function is enabled, the
appropriate I/O Pin is not available as GPIO any more. Handshaking functions are generally enabled
per default. Wi-Fi coexistence functions are currently not used. But if they should be used or
required in the future, the appropriate function cannot be moved to another I/O Pin. Hence it
should be considered that no other user function is assigned to an I/O Pin if the coexistence
functions are required. The following table lists all GPIOs and their alternative functions.
Table 3-19: GPIO - Alternative Functions BTM410/411
GPIO Pin
(BTM410/411)
Alternative Function
Handshaking Wi-Fi Coexistence
GPIO1 RI -
GPIO2 DCD -
GPIO3 - BT_Priority / Ch_Clk
GPIO4 - BT_Active / BT_State
GPIO5 - Wlan_Active
GPIO6 - Rf_Active
GPIO7 DTR -
GPIO8 DSR -