Previous Thread
Next Thread
Print Thread
Page 65 of 67 1 2 63 64 65 66 67
#112201 - 01/16/18 11:57 AM Re: New dumps [Re: rfka01]  
Joined: Feb 2004
Posts: 1,906
Vas Crabb Online content
Very Senior Member
Vas Crabb  Online Content
Very Senior Member

Joined: Feb 2004
Posts: 1,906
Sydney, Australia
Originally Posted by rfka01
The oscillator is labeled 4194.304 kHz.

Thanks. Interesting that the oscillator/clock divider chip is nowhere near the crystal. You'd think that would be a recipe for instability.

#112202 - 01/16/18 01:10 PM Re: New dumps [Re: Darkstar]  
Joined: Feb 2004
Posts: 1,906
Vas Crabb Online content
Very Senior Member
Vas Crabb  Online Content
Very Senior Member

Joined: Feb 2004
Posts: 1,906
Sydney, Australia
Sorry to be a pain, but can you measure voltages and/or frequencies on the board while it's running, or measure continuity? I'm interested in what's going on with the clock generator chip - the Intel P4201A (16-pin chip near the big D4289 8-bit memory controller).
  • If you can measure voltages, check the voltage on pin 5 with respect to pin 15
  • If you can measure frequencies, check the frequency coming out on pin 3 (MOS compatible) and the crystal frequency on pin 7 or pin 8
  • If you can measure continuity (with the machine off), check whether pin 5 is connected to pin 15 or pin 4

#112203 - 01/16/18 01:37 PM Re: New dumps [Re: Darkstar]  
Joined: Jan 2012
Posts: 863
rfka01 Offline
Senior Member
rfka01  Offline
Senior Member

Joined: Jan 2012
Posts: 863
Bavaria
The voltage regulators and several Tantals look shot so I can't / dare not turn it on in this state.

On the P4201A, pin 5 and 15 are connected.


NCR DMV- DEC Rainbow- Siemens PCD- ITT 3030-Oly People- Acorn A5000- Olivetti M20
#112204 - 01/16/18 03:28 PM Re: New dumps [Re: rfka01]  
Joined: Feb 2004
Posts: 1,906
Vas Crabb Online content
Very Senior Member
Vas Crabb  Online Content
Very Senior Member

Joined: Feb 2004
Posts: 1,906
Sydney, Australia
Originally Posted by rfka01
On the P4201A, pin 5 and 15 are connected.

OK, we know it's in divide-by-seven mode anyway. Let's assume it's used to generate the CPU clock.

#112506 - 02/06/18 04:59 AM Re: New dumps [Re: Darkstar]  
Joined: May 2009
Posts: 1,664
Just Desserts Offline
Very Senior Member
Just Desserts  Offline
Very Senior Member

Joined: May 2009
Posts: 1,664
Would someone be so kind as to add this dump from a Casio SK-1 to MAME, so that it doesn't get lost? https://spun.io/wp-content/uploads/2018/02/sk1-rom-raw.zip

#112507 - 02/06/18 05:21 AM Re: New dumps [Re: Just Desserts]  
Joined: Feb 2004
Posts: 1,906
Vas Crabb Online content
Very Senior Member
Vas Crabb  Online Content
Very Senior Member

Joined: Feb 2004
Posts: 1,906
Sydney, Australia
Originally Posted by Just Desserts
Would someone be so kind as to add this dump from a Casio SK-1 to MAME, so that it doesn't get lost? https://spun.io/wp-content/uploads/2018/02/sk1-rom-raw.zip

I'll add it. MSM6283 apparently.

#112537 - 02/08/18 06:17 PM Re: New dumps [Re: Darkstar]  
Joined: Mar 2005
Posts: 498
incog Offline
Senior Member
incog  Offline
Senior Member

Joined: Mar 2005
Posts: 498
Bradford, UK

#112538 - 02/08/18 07:20 PM Re: New dumps [Re: incog]  
Joined: Oct 2006
Posts: 956
Stiletto Offline
Senior Member
Stiletto  Offline
Senior Member

Joined: Oct 2006
Posts: 956

Last edited by Stiletto; 02/08/18 07:21 PM.
#112539 - 02/08/18 07:38 PM Re: New dumps [Re: Darkstar]  
Joined: Mar 2005
Posts: 498
incog Offline
Senior Member
incog  Offline
Senior Member

Joined: Mar 2005
Posts: 498
Bradford, UK
If they did provide it, which i assume so too, it's not linked on their site.

#112542 - 02/08/18 09:37 PM Re: New dumps [Re: incog]  
Joined: Oct 2006
Posts: 956
Stiletto Offline
Senior Member
Stiletto  Offline
Senior Member

Joined: Oct 2006
Posts: 956
Originally Posted by incog
If they did provide it, which i assume so too, it's not linked on their site.


I thought it might be inside the SDK - but it seems not. Indeed, it is not leaping out at me right now.

Page 65 of 67 1 2 63 64 65 66 67

Who's Online Now
5 registered members (MarkBielman, Dorando, EoceneMiacid, Edstrom, 1 invisible), 28 guests, and 0 spiders.
Key: Admin, Global Mod, Mod
Shout Box
Forum Statistics
Forums9
Topics8,496
Posts110,806
Members4,781
Most Online225
May 26th, 2014
Powered by UBB.threads™ PHP Forum Software 7.6.0
Page Time: 0.041s Queries: 14 (0.018s) Memory: 5.0276 MB (Peak: 5.2756 MB) Zlib enabled. Server Time: 2018-02-22 16:24:50 UTC