I've got a MegaST2, which isn't properly working. When I switch on the machine, I only have a black screen. When I switch it on with the floppy drive disconnected, there is a flickering screen for a couple of seconds before it goes black.
However when I shortcircuit pin 17 and 18 of the CPU, it'll boot, but there are no icons on the desktop while the menu works correctly.
Someone before me soldered a mod ontop of the CPU as you can see in the picture below:
Please help. What can I do to solve this issue?
MegaST2 won't start up properly
Re: MegaST2 won't start up properly
I forgot:
Pin 18 shows 5Volts on a multimeter
Pin 17 just 0Volt
Pin 18 shows 5Volts on a multimeter
Pin 17 just 0Volt
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Re: MegaST2 won't start up properly
The mod is a factory installed blitter patch.
Clearly you already suspect the reset circuitry. Have you tried checking U2 7407?
Clearly you already suspect the reset circuitry. Have you tried checking U2 7407?
Re: MegaST2 won't start up properly
Sorry, I'm a n00b to hardware and electronics...
what is "U2 7407"? And what to check?
what is "U2 7407"? And what to check?
Re: MegaST2 won't start up properly
Broken reset switch ? Check RESET with meter to GND and press and hold reset button.. voltage should change between 0V and 5V.
https://www.exxosforum.co.uk/atari/ All my hardware guides - mods - games - STOS
https://www.exxosforum.co.uk/atari/store2/ - All my hardware mods for sale - Please help support by making a purchase.
viewtopic.php?f=17&t=1585 Have you done the Mandatory Fixes ?
Just because a lot of people agree on something, doesn't make it a fact. ~exxos ~
People should find solutions to problems, not find problems with solutions.
https://www.exxosforum.co.uk/atari/store2/ - All my hardware mods for sale - Please help support by making a purchase.
viewtopic.php?f=17&t=1585 Have you done the Mandatory Fixes ?
Just because a lot of people agree on something, doesn't make it a fact. ~exxos ~
People should find solutions to problems, not find problems with solutions.
Re: MegaST2 won't start up properly
Tried to. Reset switch seems to be broken. What to do now?
Re: MegaST2 won't start up properly
Replace the switch ?
https://www.exxosforum.co.uk/atari/ All my hardware guides - mods - games - STOS
https://www.exxosforum.co.uk/atari/store2/ - All my hardware mods for sale - Please help support by making a purchase.
viewtopic.php?f=17&t=1585 Have you done the Mandatory Fixes ?
Just because a lot of people agree on something, doesn't make it a fact. ~exxos ~
People should find solutions to problems, not find problems with solutions.
https://www.exxosforum.co.uk/atari/store2/ - All my hardware mods for sale - Please help support by making a purchase.
viewtopic.php?f=17&t=1585 Have you done the Mandatory Fixes ?
Just because a lot of people agree on something, doesn't make it a fact. ~exxos ~
People should find solutions to problems, not find problems with solutions.
Re: MegaST2 won't start up properly
How? Do you sell any switches? Let's say, I don't necessarily need the switch. Can I just remove it?
- rubber_jonnie
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Re: MegaST2 won't start up properly
You mentioned earlier that you weren't too great with electronic stuff and hardware, so don't do this if you aren't competent at soldering.
Exxos has switches here: https://www.exxosforum.co.uk/atari/store2/#0114
Collector of many retro things!
800XL and 65XE both with Ultimate1MB,VBXL/XE & PokeyMax, SIDE3, SDrive Max, 2x 1010 cassette, 2x 1050 one with Happy mod, 3x 2600 Jr, 7800 and Lynx II
Approx 20 STs, including a 520 STM, 520 STFMs, 3x Mega ST, MSTE & 2x 32 Mhz boosted STEs
Plus the rest, totalling around 50 machines including a QL, 3x BBC Model B, Electron, Spectrums, ZX81 etc...
800XL and 65XE both with Ultimate1MB,VBXL/XE & PokeyMax, SIDE3, SDrive Max, 2x 1010 cassette, 2x 1050 one with Happy mod, 3x 2600 Jr, 7800 and Lynx II
Approx 20 STs, including a 520 STM, 520 STFMs, 3x Mega ST, MSTE & 2x 32 Mhz boosted STEs
Plus the rest, totalling around 50 machines including a QL, 3x BBC Model B, Electron, Spectrums, ZX81 etc...
Re: MegaST2 won't start up properly
Don't worry, my neighbour studied physics and technical computer science. He'll make it. Ordered the switch