Previous Thread
Next Thread
Print Thread
Page 1 of 4 1 2 3 4
#102087 - 10/19/15 03:52 PM Epoch Cassette Vision and uPD77X chips  
Joined: Aug 2009
Posts: 169
plgDavid Offline
Senior Member
plgDavid  Offline
Senior Member

Joined: Aug 2009
Posts: 169
Montreal
SlyDC just updated his blog with a bit more info:
http://discreteconsoles.blogspot.ca/2015/10/nec-upd774c.html

He's traced the pins of the NEC all in one micro, (thanks!)

#102088 - 10/19/15 04:05 PM Re: Epoch Cassette Vision and uPD77X chips [Re: plgDavid]  
Joined: Mar 2008
Posts: 1,029
Shideravan Offline
Very Senior Member
Shideravan  Offline
Very Senior Member

Joined: Mar 2008
Posts: 1,029
Awesome! laugh


"A user interface is like a joke. If you have to explain it, it's not that good."
#102089 - 10/19/15 04:49 PM Re: Epoch Cassette Vision and uPD77X chips [Re: plgDavid]  
Joined: Mar 2006
Posts: 1,007
Lord Nightmare Offline
Very Senior Member
Lord Nightmare  Offline
Very Senior Member

Joined: Mar 2006
Posts: 1,007
PA, USA
PlgDavid: can you ask slydc to flip the pcb over in this pic: http://1.bp.blogspot.com/-S0V0h08qeQ8/ViRDlpe0uPI/AAAAAAAAASc/NLHVDKUgaCw/s1600/battle%2Bvader.jpg and take a picture of the back?

The 'two missile pins' and 'two start pins' thing is confusing. Are they shorted together when the button is pushed?

LN


"When life gives you zombies... *CHA-CHIK!* ...you make zombie-ade!"
#102092 - 10/19/15 05:13 PM Re: Epoch Cassette Vision and uPD77X chips [Re: plgDavid]  
Joined: Aug 2009
Posts: 169
plgDavid Offline
Senior Member
plgDavid  Offline
Senior Member

Joined: Aug 2009
Posts: 169
Montreal
No need here are scans of mine (after removing the chip)



Last edited by plgDavid; 10/19/15 05:14 PM.
#102094 - 10/19/15 05:17 PM Re: Epoch Cassette Vision and uPD77X chips [Re: plgDavid]  
Joined: Aug 2009
Posts: 169
plgDavid Offline
Senior Member
plgDavid  Offline
Senior Member

Joined: Aug 2009
Posts: 169
Montreal
And the Cassette Vision JR PCB scan




#102095 - 10/19/15 05:19 PM Re: Epoch Cassette Vision and uPD77X chips [Re: plgDavid]  
Joined: Aug 2009
Posts: 169
plgDavid Offline
Senior Member
plgDavid  Offline
Senior Member

Joined: Aug 2009
Posts: 169
Montreal

#102100 - 10/19/15 07:32 PM Re: Epoch Cassette Vision and uPD77X chips [Re: plgDavid]  
Joined: Mar 2006
Posts: 1,007
Lord Nightmare Offline
Very Senior Member
Lord Nightmare  Offline
Very Senior Member

Joined: Mar 2006
Posts: 1,007
PA, USA
On the cartridge:
capacitor C01, I see one leg connects to upd pin 18; where does the other leg go?
Also what are the markings on capacitors C01 thru C04?
Also is resistor R02 5.6K or 5.7K? the stripe is poorly visible.
Also are there any markings on R04 to show what value/type of resistor pack it is?

LN

Last edited by Lord Nightmare; 10/19/15 07:34 PM. Reason: add question about R04

"When life gives you zombies... *CHA-CHIK!* ...you make zombie-ade!"
#102102 - 10/19/15 08:29 PM Re: Epoch Cassette Vision and uPD77X chips [Re: plgDavid]  
Joined: Mar 2006
Posts: 1,007
Lord Nightmare Offline
Very Senior Member
Lord Nightmare  Offline
Very Senior Member

Joined: Mar 2006
Posts: 1,007
PA, USA
Here's my hacked together diagram so far of the pinout:

https://dl.dropboxusercontent.com/u/79094972/uPD77x_pinout.txt


"When life gives you zombies... *CHA-CHIK!* ...you make zombie-ade!"
#102103 - 10/19/15 09:47 PM Re: Epoch Cassette Vision and uPD77X chips [Re: plgDavid]  
Joined: Aug 2009
Posts: 169
plgDavid Offline
Senior Member
plgDavid  Offline
Senior Member

Joined: Aug 2009
Posts: 169
Montreal
C01 1uF 50v (neg terminal goes to ground)
C02 10uF 16v
C03 1200pF (122)
C04 47nF (473)
R02 is green brown red gold (hence 5.1k Ohms 5%)
R04 7X682M

Last edited by plgDavid; 10/19/15 09:48 PM. Reason: typo
#102105 - 10/19/15 11:31 PM Re: Epoch Cassette Vision and uPD77X chips [Re: plgDavid]  
Joined: Mar 2006
Posts: 1,007
Lord Nightmare Offline
Very Senior Member
Lord Nightmare  Offline
Very Senior Member

Joined: Mar 2006
Posts: 1,007
PA, USA
Updated, thanks!


"When life gives you zombies... *CHA-CHIK!* ...you make zombie-ade!"
Page 1 of 4 1 2 3 4

Who's Online Now
4 registered members (EoceneMiacid, Dorando, Edstrom, 1 invisible), 26 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: 0.028s Queries: 14 (0.007s) Memory: 5.0162 MB (Peak: 5.2446 MB) Zlib enabled. Server Time: 2018-02-22 16:24:07 UTC