MegaSTE flashing keyboard light only
Re: MegaSTE flashing keyboard light only
What does 12v power anyway ? If its nothing much, pull the 12v wire out of the connector and see if there is any life ?
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.
-
TheNameOfTheGame
- Posts: 165
- Joined: Tue Dec 05, 2017 5:49 pm
- Location: Almost Heaven, West Virginia
Re: MegaSTE flashing keyboard light only
Exactly. That was my thought also. Pull the 12V wire and see if it comes to life.
Re: MegaSTE flashing keyboard light only
I can only find 1 circuit in the schematics that shows the 12v on the board and I have no idea what it does.
So I will give that a go.
James
So I will give that a go.
James
Re: MegaSTE flashing keyboard light only
- 12vpic.jpg (31.24 KiB) Viewed 2707 times
Ok, so 12v and -12 goes to the 1488 U311 - which is involved in the Serial communications.. if Serial io is bad then 1488 is a possible cause.
The 1488 after looking it up is driven by 7-15 volts. SO it needs the 12 and -12. Now I am not looking at a board .. but need to see if U311 which is a 14pin DIP package is socketed (doubt it) also finding one might be difficult.
Opinions?
James
Re: MegaSTE flashing keyboard light only
Pull the 12v wire then.. It may power parts of the audio circuit as well..
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: MegaSTE flashing keyboard light only
Well the board did power.. the psu started up.. fan on.. tries to initate the screen.. NO.. flashing.. black to white.. again again..
James
James
-
rubber_jonnie
- Site Admin
- Posts: 10641
- Joined: Thu Aug 17, 2017 7:40 pm
- Location: Essex
- Contact:
Re: MegaSTE flashing keyboard light only
I doubt the 12v is the problem, even if the serial chip was dead, it'd have to be a dead short to kill it. and I don't think it would cycle like that. ST's run on just 5V so it should work with no 12V feeds at all.
I can't recall, have you checked the reset switch hasn't failed on?
Also, and again, I don't recall if you did this, but does it work without the keyboard? could there be a KBD fault causing the CTRL+ALT+DEL signal causing a reset?
I can't recall, have you checked the reset switch hasn't failed on?
Also, and again, I don't recall if you did this, but does it work without the keyboard? could there be a KBD fault causing the CTRL+ALT+DEL signal causing a reset?
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: MegaSTE flashing keyboard light only
No reset works fine, it does pause all this.. let it go .. starts flashing again.
No keyboard connected at the moment.
James
No keyboard connected at the moment.
James
Re: MegaSTE flashing keyboard light only
It may need 12V to work.. but at least you know you need to find that 12V short now to get it to power up at least..
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: MegaSTE flashing keyboard light only
Looks like +12 is used in a couples places beyond the rs232 chips. It powers a regulator that powers a audio device. Also supplies power to J902. I don't know if I would use a pc supply. It may deliver so much current it could burn the traces off your MSTE board.
- Pasted Graphic.png (86.8 KiB) Viewed 2643 times