Forgottenmyname - Progress

Where Alpha builders can post pics and progress etc
Post Reply
User avatar
exxos
Site Admin
Site Admin
Posts: 23498
Joined: Wed Aug 16, 2017 11:19 pm
Location: UK
Contact:

Re: Forgottenmyname - Progress

Post by exxos »

Forgottenmyname wrote: Thu Sep 20, 2018 6:34 pm My PSU needed a quick tweak, was running at 4.93 between 7 and 14 of the LS11 which was the same value on the floppy power connector
Thats good then...

I would check resistance of the whole address and databus (power off of course) Each resistor pack pin to 5V and make sure you have 2.2K on each one..

The address bus resistor packs 4,6,8..

Databus packs 2,3.

Also check
/AS on GLUE (pin 34)..
UDS (pin 47)
LDS (pin 46)
R/W (pin 55)

Also check those pins with power on (voltage scope) see what they are doing..
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.
User avatar
PhilC
Moderator
Moderator
Posts: 6016
Joined: Fri Mar 23, 2018 8:22 pm

Re: Forgottenmyname - Progress

Post by PhilC »

Just checking now. First thing i notice is some of my resistor packs are 4.7K, no 2.2K ones.

I don't suppose that makes a difference?

will check the datalines etc next
If it ain't broke, test it to Destruction.
User avatar
exxos
Site Admin
Site Admin
Posts: 23498
Joined: Wed Aug 16, 2017 11:19 pm
Location: UK
Contact:

Re: Forgottenmyname - Progress

Post by exxos »

4.7k is fine.
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.
User avatar
PhilC
Moderator
Moderator
Posts: 6016
Joined: Fri Mar 23, 2018 8:22 pm

Re: Forgottenmyname - Progress

Post by PhilC »

exxos wrote: Thu Sep 20, 2018 6:34 pm
Also check
/AS on GLUE (pin 34)..
UDS (pin 47)
LDS (pin 46)
R/W (pin 55)

Also check those pins with power on (voltage scope) see what they are doing..
Ok, all the resistances seem ok to 5v, checked the cpu to mmu address lines ok.
checked glue to cpu data lines ok
/AS is 1mhz square wave,
/AS on Glue is 2mhz square wave
UDS,LDS and R/W all high.
If it ain't broke, test it to Destruction.
User avatar
exxos
Site Admin
Site Admin
Posts: 23498
Joined: Wed Aug 16, 2017 11:19 pm
Location: UK
Contact:

Re: Forgottenmyname - Progress

Post by exxos »

Forgottenmyname wrote: Thu Sep 20, 2018 8:52 pm Ok, all the resistances seem ok to 5v, checked the cpu to mmu address lines ok.
checked glue to cpu data lines ok
/AS is 1mhz square wave,
/AS on Glue is 2mhz square wave
UDS,LDS and R/W all high.
What is the address and databus doing on the scope ?

Address bus should all be low to read the first byte in ROM... You may have to keep pressing reset or setup a trigger on your scope as even ROM OE might pulse low once after reset without you seeing it ?
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.
User avatar
PhilC
Moderator
Moderator
Posts: 6016
Joined: Fri Mar 23, 2018 8:22 pm

Re: Forgottenmyname - Progress

Post by PhilC »

Ok, will have a look tomorrow, she who must be obeyed is calling.
If it ain't broke, test it to Destruction.
User avatar
Icky
Site Admin
Site Admin
Posts: 3986
Joined: Sun Sep 03, 2017 10:57 am
Location: UK

Re: Forgottenmyname - Progress

Post by Icky »

Hi - How are you getting along?

Would like to see if your board is in the same state mine is - if you are seeing bombs with that weird shifting pattern or something else.

Icky
User avatar
PhilC
Moderator
Moderator
Posts: 6016
Joined: Fri Mar 23, 2018 8:22 pm

Re: Forgottenmyname - Progress

Post by PhilC »

Not yet icky but hope to have some more progress later tonight.

I'm just wondering if the main difference has been that I'm using the mum ram instead of the falcon ram?
If it ain't broke, test it to Destruction.
User avatar
exxos
Site Admin
Site Admin
Posts: 23498
Joined: Wed Aug 16, 2017 11:19 pm
Location: UK
Contact:

Re: Forgottenmyname - Progress

Post by exxos »

Can you post a image on how you have fitted the ram board ?
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.
User avatar
PhilC
Moderator
Moderator
Posts: 6016
Joined: Fri Mar 23, 2018 8:22 pm

Re: Forgottenmyname - Progress

Post by PhilC »

exxos wrote: Fri Sep 21, 2018 6:49 pm Can you post a image on how you have fitted the ram board ?
Here we go.
Attachments
20180921_193241.jpg
20180921_193241.jpg (3.95 MiB) Viewed 3210 times
If it ain't broke, test it to Destruction.
Post Reply

Return to “ALPHA USER BUILDS”