Commodore Techtopics, Issue 15, 1985: Disk Drive 4

Issue 15, 1985 : Disk Drive 4

Model: 1541

RE: COMMON FAILURE SYPTOM: DRIVE RUNS CONTINUOSLY.

TROUBLESHOOOTING GUIDE:

1) Check system RESET - 6502, Pin 40

2) Check system RINS

3) Check 7417 driver - UD2

4) Check R/W - Must be LOW (Not above 4.0V)

5) Check for cold solder joint at J7 (Newtronics only)

6) Check MTR signal - UC2, 6522

7) Check _MTR signal - UC1, PLA

NUMEROUS CALLS HAVE COME IN TO THE TECH HOT LINE CONCERNING THIS FAILURE INDICATION.

PLEASE REFER TO THIS CHECK LIST BEFORE CALLING FOR HELP.

This page has been created by Sami Rautiainen.
Read the small print.	Last updated January 20, 2006.

1)	Check system RESET - 6502, Pin 40
2)	Check system RINS
3)	Check 7417 driver - UD2
4)	Check R/W - Must be LOW (Not above 4.0V)
5)	Check for cold solder joint at J7 (Newtronics only)
6)	Check MTR signal - UC2, 6522
7)	Check _MTR signal - UC1, PLA