Functionality Test - Alesis DEQ224 Service Manual

Functionality Test

These tests combine checks for EEPROM, LED and Switches.
1) Press the CHANNEL/EXIT and BYPASS buttons on the Known Good ME1 Front
Panel Sub-Assembly and hold these buttons during Step 2. When started
in this manner, the unit will enter Factory Test Mode.
2) Plug the P3 type Alesis Power Supply into a power source and the
barrel jack into the DUT Power In jack.
Verify that the front panel LEDs show normal power up message,
"DEQ224". After this message, "TEST" should display briefly on
the LEDs.
Problems with this inspection indicate that the unit has not
entered Factory Test Mode.
and 2.
3) As soon as the DUT enters Factory Test Mode, the EEPROM is checked.
Verify that the seven segment display DOES NOT read "EE".
display should read "00".
Problems with this inspection indicate that the EEPROM has
failed internal diagnostics.
Failure of this inspection indicates that the DUT cannot
continue further testing.
4) Press Band Button 1. This button is located on the far left hand side
of the unit, underneath the column marked "25".
LED COLUMN TEST.
Verify that columns begin to light in order.
Verify that each column lights in order without skipping any
columns. Verify that all the LEDs in a common column light at
the same time, and that two columns are NEVER on at the same
time.
LEDs turn on.
Problems with no response to Band Button 1 indicate Band Button
1 is faulty and the test has FAILED.
inspection indicate test has FAILED.
Failure of this inspection indicates that the DUT cannot
continue further testing.
Verify that when LEDs in a column are lit, that all the
Unplug the unit and repeat steps 1
This button runs the
Problems with LED
The