Click of death: Difference between revisions
Jump to navigation
Jump to search
(Created page with "The "Click of Death" is the name given to a fault which can occur on cartridge systems, most often MVS boards. A regular click/pop sound ([https://instaud.io/lCr sample]) can...") |
m (Animated gif example) |
||
| Line 1: | Line 1: | ||
[[File:Clickofdeath.gif|thumb|The picture's juming is caused by the video sync being disabled during the short reset periods.]] | |||
The "Click of Death" is the name given to a fault which can occur on cartridge systems, most often MVS boards. | The "Click of Death" is the name given to a fault which can occur on cartridge systems, most often MVS boards. | ||
The system fails to start, while a periodic click/pop sound ([https://instaud.io/lCr sample]) can be heard in the audio, if the [[audio amplifier|amplifier]] or TV volume is set loud enough. | |||
=Cause= | =Cause= | ||
The particular sound is a side effect caused by the system resetting itself (see [[watchdog]]) and causing the [[YM2610]] | The particular sound is a side effect caused by the system resetting itself (see [[watchdog]]) and causing the [[YM2610]] to output sudden voltage changes on its analog output. | ||
The | The periodicity means that the system tries to boot over and over. | ||
=Investigation= | =Investigation= | ||
| Line 13: | Line 14: | ||
The repetition rate of the click can give clues about the actual fault. | The repetition rate of the click can give clues about the actual fault. | ||
* A fast click (~ | * A fast click (~8Hz) often means that something essential doesn't work: no clock to the [[68k]], cut or shorted bus, dead work RAM, dead CPU, dead [[system ROM]], can't write to [[NEO-B1]]... | ||
* A slow click (1Hz or less) can mean that some step of the [[system self-test]] causes a crash. Address lines, | * A slow click (1Hz or less) can mean that some step of the [[system self-test]] causes a crash. Address lines, dead memory, shorted traces... | ||
* Random clicks can indicate cut, floating traces. | * Random clicks can indicate cut, floating traces. | ||
[[Category:Repairs]] | [[Category:Repairs]] | ||
Revision as of 00:10, 4 May 2016
The "Click of Death" is the name given to a fault which can occur on cartridge systems, most often MVS boards.
The system fails to start, while a periodic click/pop sound (sample) can be heard in the audio, if the amplifier or TV volume is set loud enough.
Cause
The particular sound is a side effect caused by the system resetting itself (see watchdog) and causing the YM2610 to output sudden voltage changes on its analog output.
The periodicity means that the system tries to boot over and over.
Investigation
The repetition rate of the click can give clues about the actual fault.
- A fast click (~8Hz) often means that something essential doesn't work: no clock to the 68k, cut or shorted bus, dead work RAM, dead CPU, dead system ROM, can't write to NEO-B1...
- A slow click (1Hz or less) can mean that some step of the system self-test causes a crash. Address lines, dead memory, shorted traces...
- Random clicks can indicate cut, floating traces.