Roland HP-335 Service Notes page 14

HP-335
6. Serial Interface Check
When press [Function] during this Serial Interface Check, it will jump
back to the beginning of the Test Mode (2. Device Check).
When you get into this mode, 7-SEG LED displays .
* MIDI CHECK
Set the Computer Switch on the underside of the keyboard to ''MIDI''.
The LED on the left side of the 7-SEG LED will be illuminated.
Connect MIDI In on the underside of the keyboard and MIDI Out on the
rear panel. If there is no malfunction, the following is displayed on the
7-SEG LED.
Connect MIDI In and MIDI Out on the rear panel. If there is no
malfunction, the following is displayed on the 7-SEG LED.
* COMPUTER I/F CHECK
To perform this test, a ''Computer Test Cable for SOUND CANVAS
SC-88'' (#17049906) is required. Please order this cable from the local
Roland Service Center if necessary.
1)Set the Computer Switch on the underside of the
keyboard to ''Mac''.
The LED on the right side of the 7-SEG LED will be illuminated.
Connect the Computer Test Cable to the Computer Jack on the
underside of the keyboard. Connect the oscilloscope to a white terminal
(Signal line) of Computer Test Cable and the GND to a black terminal
(GND line). Check if the 1MHz square wave appears or not.
Turn the Computer Test Cable SW to On. If there is no malfunction, the
following is displayed on the 7-SEG LED.
Turn the Computer Test Cable SW to Off. If there is no malfunction,
the following is displayed on the 7-SEG LED.
2)Set the Computer Switch on the underside of the
keyboard to ''PC1''.
The Beat LED on the right side of the 7-SEG LED will be illuminated.
Connect the Computer Test Cable to the Computer Jack on the
underside of the keyboard and turn the Computer Test Cable SW to On.
If there is no malfunction, the following is displayed on the 7-SEG
LED.
Turn the Computer Test Cable SW to Off. If there is no malfunction,
the following is displayed on the 7-SEG LED.
3)Set the Computer Switch on the underside of the
keyboard to ''PC2''.
The Song LED on the right side of the 7-SEG LED will be illuminated.
Connect the Computer Test Cable to the Computer Jack on the
underside of the keyboard and turn the Computer Test Cable SW to On.
If there is no malfunction, the following is displayed on the 7-SEG
LED.
Turn the Computer Test Cable SW to Off. If there is no malfunction,
the following is displayed on the 7-SEG LED.
It will jump to the beginning of the Test Mode (2. Device Check) by
pressing [Function] button.
7. To exit the Test Mode
To exit the Test Mode, turn the power Off.
8. Microphone Check
After executing the Test Mode, turn the power On again and connect a
Microphone to the Mic In Jack on the underside of the keyboard.
Confirm if it functions correctly or not by turning the Echo Knob and
Volume Knob near the Mic In Jack.
14
Nov. 1998