Volume buttons on the Tx and Rx will increase/decrease the volume audio
level by 1dB per button press for a total of 70 steps. Pressing and holding
a volume button will ramp the volume quickly. Maximum volume is 0dB
and minimum volume is -70dB. NOTE: Volume settings are stored and
recalled on reboots. (Normal Default Setting: Max for both channels)
D. RF Mating:
A Tx node and an Rx node will not connect to each
other unless they have the same 16 bit Mating ID stored in their
respective parameter pages. Out of the box, the HT evaluation kit is
already pre-mated. RF Mating is the procedure of matching (or re-
matching) the 16 bit Mating ID of 2 or more nodes.
RF Mating is usually initiated by pressing and holding the RF Mating
button on the Tx for more than 3 seconds until the Tx bond LED flashes
quickly. The Tx will then generate a 16 bit random number to use for the
new Mating ID. The Tx then attempts to mate with Rx nodes. The Rx
nodes briefly enter RF mating mode every time they are powered on, so
power must be cycled on each Rx node that you want mated to the Tx. RF
Mating has a default timeout of 1 minute. If the Tx does not find any Rx
nodes before the timeout it will terminate RF Mating mode and revert
back to the previous Mating ID. If successful mating occurs before timing
out, the number of Rx nodes that mate to the Tx will define the new
topology after RF Mating has timed out or completed (i.e., 2-Node or 3-
Node).
E. Audio Level Standby:
The Audio Level Standby Feature is
implemented on the TX node. This feature is implemented in order to
reduce power consumption when the audio level drops below a
particular threshold. When the audio level drops below this threshold for
a predetermined amount of time, the Tx sends a sleep command to the
Rx. The Rx will then enter a low power sleep mode and will wait for the
audio level to rise above the threshold. (Normal Default Setting: 78
seconds)
F. Reset Button:
Pressing the Reset button will reset the entire
module. This button is sometimes useful when downloading new
firmware.
G. XPD Port Interface:
The XInC Programming and Debugging
(XPD) port is used to download firmware hex files to the HT-222 module,
using an XPD Programming Module (available from Eleven Engineering).
For more information regarding the XPD Port, XPD Module, and the
procedure for programming modules refer to the document
“Downloading Firmware to XInC Processors” (Available from Eleven
Engineering).
H. Two Wire Serial Interface (TWSI):
The HT system
incorporates an I2C compatible two wire control interface, used to
configure the system’s optional settings. The TWSI also provides
developers with a method to transfer data over the wireless link.
i)
TWSI controls:
HT settings (buffer size, audio mode, mating ID,
etc.) may be programmed via TWSI; however, when these settings
are adjusted most will trigger a system reset. Some settings meant
for real time controls (volume and mute control, etc.) can be set live
without triggering a reset.
ii) Pass-through TWSI data channel:
User data sent into the
audio Tx is directly output “as-is” from the audio Rx and similarly for
the reverse direction (Rx to Tx).
NOTE: When using a custom external audio chip, fundamental firmware
modifications may be required to configure the chip registers. These changes
can not be done with the TWSI.
I. Parameter Pages:
The HT system comes pre-loaded with a parameter
page that configures the default functionality of the system. Some of the
commonly changed registers are listed below.
Addr 00/01
Mating ID number
Addr 02
RF Configuration (RF mating, Static ID, Dynamic Mating)
Addr 03
Buffer Size (Latency)
Addr 06
General Configuration (TWSI Mode, TWSI Interrupt Enabled, Sleep, Noise
Gate)
Addr 0E
Audio Configuration (Stereo, Right Channel, Left Channel, Local/Global
Volume mode, l2S/Left-Justified mode)
www.ElevenEngineering.com
HT-222 Evaluation Kit Instructions
DO4927|
2009.11.05
Page 2/4
