Bose T1 ToneMatch, Руководство по обслуживанию

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USB Input/Output
The T1 provides a USB interface for connection to a Windows
®
PC. The interface will enable:
a) audio streaming from the PC to the T1
b) audio streaming from the T1 to a PC
c) Updates of firmware, data sets and features
d) Backup of user defined scenes and configurations
Upon initial connection the T1 will appear as a standard USB audio device. Audio streaming is
possible through any standard Windows audio application that is capable of communicating with
a standard audio device.
The update features is implemented through a proprietary Human Device Interface (HID) class
interface. This requires a Bose
® provided PC application.
USB audio streaming supports bi-directional. USB incoming audio is summed to mono and
routed either to the master summer or added to the channel 4/5 inputs.
The outgoing USB signals are determined through two independent multiplexer. Each output
can be selected from six different tap points: Channel 1, 2, 3, 4/5, aux sum, or master sum. All
channel taps and the master tap are post-fade.
DC Power
A n/-18VDC is brought in through J12. This can be created by an external power
supply when the T1 is used without the L1 Model II power stand, or it can come from the L1
Model II. When the power stand supplies the voltage, it can range from +/- 16 to 29 VDC.
U1 and U4 switch the +/-18 V to +/-15VDC for audio and LED power.
U23 provides 5VDC, which is in turn linearly regulated down to 3.3V for the DSP I/O supply.
A 1.2V, 500 mA supply is also generated directly form the +18V rail, to supply the DSP core.
Switch 2 turns on the +48V supply for phantom power, which is applied to each microphone
input through a 1K resistor and two 4.99K resistors to pins 2 and 3 of the microphone connector.
This allows up to 14 mA of current into condenser mics.
Software Updates
Please see the Bose L1 Updater instructions for how to update T1 and L1 Model II power stand
firmware.
Buses
DSP – CODECs
Audio is passed between DSP and Codec’s with an I
2 S bus labeled DSP_BICK, DSP_LRCLK,
SDIN and SDOUT.
CODEC control is accomplished through the DSP’s primary and secondary SPI busses (for U20
and U21, respectively) on dedicated pins labeled SPI_MISO_A, SPI_CLK_A, SPI_MOSI_A, and
SPI_MISO_B, SPI_CLK_B, SPI_MOSI_B
DSP – Boot Flash
The serial boot flash also communicates with the DSP through the primary SPI bus
Theory of Operation