Bose 321 GS Home Entertainment System (US/Canada, European, UK, Australia, Japan and Dual Voltage Versions)
The 3•2•1 and 3•2•1 GS (Gemstone) home entertainment systems share the same basic components. The bass module and bass module cable are identical. The console uses the same electronic parts and most of the same chassis parts. The differences in the console are the console firmware and the color of the silver front bezel and DVD drawer bezel. The arrays used on the two systems are different. The standard 3•2•1 system uses the larger 60mm driver arrays, and are only available in graphite. The 3•2•1 GS arrays utilize the smaller 50mm Jewel Cube® driver. These arrays are available in graphite and silver.
Software Update Information
The firmware located in the main PCB and display PCB's microprocessors can be updated by means of an update CD. These update CDs are available from Bose® Product and Technical Support at 800-233-4408 (Bose service centers only) or 800-367-4008 (Bose system owners) and are automatically sent out to customers who have purchased the 3-2-1 system, filled out and returned the software update card that came with their system literature. Service centers can also download an ISO image of the latest firmware update file from the Service web site at http://serviceops.bose.com and burn it onto a CD for use as an update disc.
Once you have the CD, simply power up the console, press the stop/eject button on the console, place the update CD into the drawer and close it and the update process will begin.
When the process is complete you may remove the update CD.
Check to verify that both the display PCB firmware and the main PCB firmware have updated properly. You can do this by using the TAP commands or by a series of button presses on the console front panel.
To check the main PCB firmware from the front
panel, perform the following steps
1. Remove power from the console for at least five seconds.
2. Re-apply power, and within five seconds, press the EJECT, SKIP UP and VOLUME UP buttons all at once for at least seven seconds. You may see the display flashing during this time.
3. After seven seconds, release all of the buttons at once. You should see a display like "321 247" on the console. This example shows that version 2.47 of the main PCB firmware is installed on this particular console.
1. Remove power from the console for at least five seconds.
2. Re-apply power, and within five seconds, press the EJECT, SKIP UP and VOLUME UP buttons all at once for at least seven seconds. You may see the display flashing during this time.
3. After seven seconds, release all of the buttons at once. You should see a display like "321 247" on the console. This example shows that version 2.47 of the main PCB firmware is installed on this particular console.
Display PCB Firmware Procedure
To check the display PCB firmware from the front panel, perform the following steps:
1. Remove power from the console for at least five seconds.
2. Re-apply power, and within five seconds, press the EJECT, SKIP UP and SOURCE DOWN buttons all at once for at least seven seconds. You may see the display flashing during this time.
3. After seven seconds, release all of the buttons at once. You should see a display like "03.52:7321" on the console. This example shows that version 3.52 of the display PCB firmware is installed on this particular console.
To check the display PCB firmware from the front panel, perform the following steps:
1. Remove power from the console for at least five seconds.
2. Re-apply power, and within five seconds, press the EJECT, SKIP UP and SOURCE DOWN buttons all at once for at least seven seconds. You may see the display flashing during this time.
3. After seven seconds, release all of the buttons at once. You should see a display like "03.52:7321" on the console. This example shows that version 3.52 of the display PCB firmware is installed on this particular console.
Computer
Setup Procedure
Use this procedure to set up your IBM compatible PC for communication with the 321 system console.
1. Open a terminal window, as shown at right, in either Terminal or Hyper term, as applicable for the version of Microsoft® Windows you are using on your PC.
Use this procedure to set up your IBM compatible PC for communication with the 321 system console.
1. Open a terminal window, as shown at right, in either Terminal or Hyper term, as applicable for the version of Microsoft® Windows you are using on your PC.
2.
In the terminal window, click on FILE, then PROPERTIES. Set the properties in
the dialog box as shown at right.
3.
In the properties dialog box shown in step
2, click on CONFIGURE to set the COM1 Properties as shown at right. Click OK to return to the properties dialog box.
2, click on CONFIGURE to set the COM1 Properties as shown at right. Click OK to return to the properties dialog box.
4.
In the properties dialog box, click on the SETTINGS tab and set the controls as
at right.
Note: Be sure to check "Beep three times when connecting or disconnecting"
Note: Be sure to check "Beep three times when connecting or disconnecting"
5.
In the properties dialog box under the SETTINGS tab, click on the ASCII Setup button
and set the controls to look like the example at right. Click OK to return to
the properties dialog box.
6.
Once you have made all of the settings in the properties dialog box, click OK
to close it. You have now configured your PC to communicate with the 321 system
console. To connect to the console under test, in the terminal window, click on
CALL, then CONNECT and listen for 3 beeps. This will tell you that the PC is
connected to communicate with the console. When you have completed your
session, click on CALL, then DISCONNECT to end communication with the console.
Console TAP Commands
The 321 console can be controlled by means of test access port (TAP) commands via the 321 system TAP cable, part number 266603, from one of the computer's serial data ports to the TAP port located on the LCD display PCB. This port can be accessed from the outside of the console without disassembling the unit. You will need the TAP cable and a RS-232 to TTL converter, such as the B+B Electronics model 232LPTTL. You can purchase the converter online at
http://www.bb-elec.com.
The communication link for the TAP facility is
Via a three wire TTL electrical interface (Transmit data, Receive data, Ground).
Logically inverted receive and transmit signals from RS-232 specification.
Same asynchronous character / timing construction as RS-232 specification requires.
The computer serial data port used for communication should be configured as follows
Half-Duplex operation
9600 baud
8-bits / data character
1 stop bit
No parity
The console echoes all commands
Refer to the computer setup procedure earlier in this section for instructions.
There is no special action required to put the 321 console into TAP mode. Once power is applied TAP control may be used.
The 321 console does not respond to multiple commands simultaneously. The user must receive an acknowledgement (ack) prior to issuing the next TAP command.
The tables on the following pages list the TAP commands broken down into the various subsections of console functions.
Bass Module Troubleshooting Information
Note: Refer to the bass module amplifier board schematic sheet for the following information.
The bass module amplifier board uses two different ground potentials. When troubleshooting, be careful that you are using the correct ground (reference) point. The ground point for the power supply circuitry is at the negative (-) side of bridge BR1. When troubleshooting, be sure to reference your tests to the negative side of BR1. Be sure to float the ground on your test equipment, including your oscilloscope. You can do this by using an 3 prong to 2 prong AC adapter plug that does not have a ground pin. The ground reference used on the bass module is at a DC voltage level.
This circuitry creates the +16 VDC voltage used by the console, which is seen at the positive side of C22. The system ground point is PGND.
Common Problems
Q1 MOSFET shorts DRAIN to SOURCE. Rarely opens. If Q1 were to short, the symptom would be that the power supply output voltage at V (TP5) would be > 22 Vdc. This voltage is used by the console and could cause distortion at high volume levels or the console to shut down, or both.
Q2 and Q3 fail. PNP transistors short and open. Sometimes need to replace both at the same time instead of one at a time.
U1 Power amplifier. TDA7396 fails.
ZR1 16 V Zener diode fails. Zener ZR1 controls the turn on / turn off of Q2, Q3 and Q1.
BR1 Bridge rectifier fails.
Console
Display Test
Using this procedure, you will be able to verify that all of the console LCD elements work properly by lighting all of them at once. Use the following steps.
1. Remove AC mains power to the bass module.
2. Re-apply AC mains power to the bass module. Within 10 seconds of re-applying power, press the right hand three buttons on the top of the console at the same time. All of the LCD display segments should light as shown in the figure below.
Note: The RDS segment is used on European models only.
Using this procedure, you will be able to verify that all of the console LCD elements work properly by lighting all of them at once. Use the following steps.
1. Remove AC mains power to the bass module.
2. Re-apply AC mains power to the bass module. Within 10 seconds of re-applying power, press the right hand three buttons on the top of the console at the same time. All of the LCD display segments should light as shown in the figure below.
Note: The RDS segment is used on European models only.
