Metrohm 774 - Main Memory (RAM); Display

6.4 Diagnosis
774 Oven Sample Processor, Instructions for use
145
6.4.3 Main memory (RAM)
This diagnosis step completes a non-destructive test of the entire area of
the RAM contents (main memory).
• Prepare the unit for diagnosis (see Chap. 6.4.2).
• If necessary, press <Ð> several times until
diagnosis
>RAM test
• <ENTER>
If no errors are found, you will see the following on the display :
>RAM test
RAM test ok
• <ENTER>
6.4.4 Display
This diagnosis step allows you to check the LEDs and the display for oper-
ability.
• Prepare the unit for diagnosis (see Chap. 6.4.2).
• If necessary, press <Ð>several times until
diagnosis
>display test
• <ENTER>
After you press key <ENTER>, the program runs automatically through a test run for optical
checking of the LEDs and the display.
⇒ All LEDs blink consecutively for a brief period.
⇒ The background lighting of the display is switched off for a short period and back on again.
⇒ The power-up test pattern (each pixel active) is displayed.
⇒ Both lines of the display are cleared.
⇒ Both lines of the display consecutively display characters " # ", "H" and, lastly, "I".
⇒ Both lines display the continuous moving text
"0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ" from right to left.
• The test run can be halted and started again by pressing key <5>.
• The test is quit with key <QUIT> or <STOP>.
diagnosis
>display contrast test
• <ENTER>
After you press the <ENTER> key, the following display is shown, whereby the contrast of the
display is varied constantly between bright and dark.
>display contrast test
774 Oven Sample Proc.
• The test can be quit with key <QUIT> or <STOP>.