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Family Computer => Technical & Repair Assistance => Topic started by: gorgyrip on September 20, 2019, 05:24:40 am

Title: ram adapter error 02
Post by: gorgyrip on September 20, 2019, 05:24:40 am
What can cause this error on a ram adapter?
The disk unit and the power supply have been tested,
I tested the cable in another ram adapter and the cable is fine.
I tested the connections between the cable and the RP2C33 and they are ok.
What else can I try?
Title: Re: ram adapter error 02
Post by: xIceMan on September 20, 2019, 10:12:36 am
Try recheck the cable:
https://www.famicomworld.com/forum/index.php?topic=13586.0
Title: Re: ram adapter error 02
Post by: gorgyrip on September 20, 2019, 11:25:20 am
Quote from: xIceMan on September 20, 2019, 10:12:36 am
Try recheck the cable:
https://www.famicomworld.com/forum/index.php?topic=13586.0


I've tested this cable on another ram adapter. Now it has the cable from a working ram adapter.
There's a few resistor and diode arrays. Could the fault be on them?
Title: Re: ram adapter error 02
Post by: xIceMan on September 20, 2019, 11:51:09 am
Hmm, if the cable was confirmed to work on another RAM adapter I'd test the continuity with a multi meter and check if anything seems off.
Perhaps check the values of the resistors as well as diode check, if possible (in off state).
Title: Re: ram adapter error 02
Post by: gorgyrip on September 20, 2019, 12:03:24 pm
Quote from: xIceMan on September 20, 2019, 11:51:09 am
Hmm, if the cable was confirmed to work on another RAM adapter I'd test the continuity with a multi meter and check if anything seems off.
Perhaps check the values of the resistors as well as diode check, if possible (in off state).


I've just checked the arrays and they are good. Also there's continuity between the cable and RP2C33.
Is the a way to fake the Battery_OK on pin 37 of rp2C33?

I assume the sram and dram chips have no connection with this problem. Am I correct?
Title: Re: ram adapter error 02
Post by: 80sFREAK on September 20, 2019, 10:21:38 pm
Quote from: gorgyrip on September 20, 2019, 12:03:24 pm
Is the a way to fake the Battery_OK on pin 37 of rp2C33?
Anything is possible(c)  8)
Quote
I assume the sram and dram chips have no connection with this problem. Am I correct?
Most likely motor or voltage regulator in the "red box"
Title: Re: ram adapter error 02
Post by: gorgyrip on September 21, 2019, 01:17:50 am
I have 2 disk units, both tested with another ram adapter and they in working condition. So the problem is with this ram adapter.
Title: Re: ram adapter error 02
Post by: 80sFREAK on September 21, 2019, 11:43:56 pm
Ok. And what is the level on the pin 37 of the faulty RAM adaptor?
Title: Re: ram adapter error 02
Post by: gorgyrip on September 22, 2019, 01:55:53 am
Quote from: 80sFREAK on September 21, 2019, 11:43:56 pm
Ok. And what is the level on the pin 37 of the faulty RAM adaptor?

How can I test that? Sadly, I don't have an oscilloscope.
Title: Re: ram adapter error 02
Post by: 80sFREAK on September 22, 2019, 10:11:55 pm
Digital multimeter?  ???
Title: Re: ram adapter error 02
Post by: gorgyrip on September 23, 2019, 03:21:31 am
Quote from: 80sFREAK on September 22, 2019, 10:11:55 pm
Digital multimeter?  ???

I think I understand now.
On pin 37 I have 0V and when i insert the disk still 0V and the red light doesn't come on, disk is not spinning.  Error 02.
But on a working ram adapter when I insert the disk it goes from 0V to 2.29V.
Title: Re: ram adapter error 02
Post by: 80sFREAK on September 27, 2019, 05:49:44 am
Any progress?  ???
Title: Re: ram adapter error 02
Post by: gorgyrip on September 27, 2019, 11:18:10 am
Sadly no.
Title: Re: ram adapter error 02
Post by: ericj on September 27, 2019, 11:55:13 am
I'd just buy another ram adapter. Gamedoctorhk.com or tototek.com can get you a tested, working one.
Title: Re: ram adapter error 02
Post by: gorgyrip on September 27, 2019, 12:40:26 pm
I have other ram adapters. I was just hoped there was a fix for this one.
Title: Re: ram adapter error 02
Post by: 80sFREAK on September 27, 2019, 10:44:31 pm
THERE IS fix(apart from dead 2C33, say, blown clamp diode on pin 37 INSIDE the chip), but it's up to you.
Title: Re: ram adapter error 02
Post by: gorgyrip on September 28, 2019, 08:52:32 am
Can i use 1N4148? And how?
Title: Re: ram adapter error 02
Post by: 80sFREAK on September 29, 2019, 02:17:56 am
Ummm... look, if internal diode short cuted, you can not do anything, but replace 2C33(say trash adaptor, or use it as donor of RAM). Try to figure out, if there is no "power good" signal generated at all or broken trace somewhere.
Title: Re: ram adapter error 02
Post by: gorgyrip on September 29, 2019, 03:21:16 pm
I undestand now. thank you.
Title: Re: ram adapter error 02
Post by: 80sFREAK on October 07, 2019, 07:13:33 am
Any progress?  ???
Title: Re: ram adapter error 02
Post by: gorgyrip on October 11, 2019, 02:16:45 pm
I gave up.
Title: Re: ram adapter error 02
Post by: 80sFREAK on October 18, 2019, 07:19:41 am
So fast  :( I expected success story  ???