derkom's attempt
Re: derkom's attempt
Here's a picture so you can see the board and jumpers, but I've triple checked them. Doesn't hurt to have a few more eyes on it though. One thing I haven't checked is to make sure the shunts are actually shorting them, but there's no reason to imagine otherwise. I'll verify that when I pull the board out to look at the soldering again.
Am I remembering incorrectly, or is it not expected to see one bus error during TOS boot, when it determines RAM size?
EDIT: I haven't stock a clock battery in, but that shouldn't matter, should it?
Re: derkom's attempt
This is the startup..
https://www.exxosforum.co.uk/forum/viewt ... =77&t=1203
I don't know how far it has to go before it sizes RAM.. if that's the case, you should be able to boot from the diagnostic cart.
https://www.exxosforum.co.uk/forum/viewt ... =77&t=1203
I don't know how far it has to go before it sizes RAM.. if that's the case, you should be able to boot from the diagnostic cart.
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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.
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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: derkom's attempt
Oh right, that's a good point. It's going to check for the diagnostic cart before the expected bus error (and no, I didn't have the diag cart inserted when capturing that data--presumably it would generate the same bus error since it sizes RAM itself).exxos wrote: ↑Thu Nov 28, 2019 7:43 pm This is the startup..
https://www.exxosforum.co.uk/forum/viewt ... =77&t=1203
I don't know how far it has to go before it sizes RAM.. if that's the case, you should be able to boot from the diagnostic cart.
Since I don't actually know what's on my TOS chip, and I would like one of the "proper" crystals (and our postal strike has mercifully ended), I'll order these from your re-energised shop. At least I can eliminate that unknown factor, if this hasn't all managed to make sense in the meantime. And we can see if the order takes 12 hours to appear.
Re: derkom's attempt
If the TOS chip is unknown, then you need to read it contents to see what version it is..derkom wrote: ↑Thu Nov 28, 2019 7:58 pm Since I don't actually know what's on my TOS chip, and I would like one of the "proper" crystals (and our postal strike has mercifully ended), I'll order these from your re-energised shop. At least I can eliminate that unknown factor, if this hasn't all managed to make sense in the meantime. And we can see if the order takes 12 hours to appear.
OK for order, will keep a closer eye on it know I got a heads up...
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: derkom's attempt
...or if there is anything there at all. I did order a EEPROM programmer so I'd be ready for the upcoming GAL work, and it'll come with an appropriate adapter for this chip as well, but it's lost somewhere between China and here at the moment, so not of much use right now.
Just placed. Naturally I managed to find a couple of other essential items as well. Got the confirmation email myself immediately.OK for order, will keep a closer eye on it know I got a heads up...
Re: derkom's attempt
Got the order.. Very odd goings on.
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: derkom's attempt
Okay, I've done this, and when the machine is in reset, I'm getting 0V on D1, D2, D3. All other data and address lines show the anticipated 5V.
This isn't a simple case of "not connected", though, because these data lines are active during a boot attempt:
I don't include RESET in that screengrab, but it's low (i.e. button held in) up until the moment where D1-D3 jump high.
Any thoughts on this? Can anyone else observe the behaviour of these lines during reset?
EDIT: And yes, I've confirmed pullups are good all the way across the bus.
Re: derkom's attempt
As they are switching high and low then should be OK. I can't find in the 68000 manual what state the pins are in during reset.. I just assumed they would go tri-state and go HI.. maybe not then..
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: derkom's attempt
Finally found it..
According to this, the databus should go tri-state and float high... Think someone else would have to verify this behavior...
According to this, the databus should go tri-state and float high... Think someone else would have to verify this behavior...
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: derkom's attempt
Oh I thought it was the whole databus... Have you double checked you have 2.2K resistance on D1-3 ?
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.