[Coco] Help with Nitros9 on SDC?

Don Barber don at dgb3.net
Wed Jan 12 09:35:08 EST 2022


Morning folks,

Pretty sure I've narrowed this down to a bad CocoSDC.

I compiled the StreamTest.asm code from the CocoSDC manual.
When I exec it, I get the same behavior as when I try to load EOU, eg 
about 5% of the time it works, the rest of the time the machine locks 
up, resets, shows gibberish on the screen, goes into a weird pmode, or 
some combination of the above. So something is making the CocoSDC write 
to the wrong memory address(es). The behavior is the same either with 
the MPI or direct to the cartridge port.

Any thoughts on if this could be a bad cartridge IO chip inside the coco 
(I'll admit my ignorance as to the internals), or just a bad CocoSDC?

If anyone has a spare CocoSDC I could borrow (I'll pay shipping both 
ways) before I drop $50 on another one, I'd appreciate it. I'm in 
central Maryland.

Thanks,

Don

On 1/9/22 4:52 PM, Don Barber wrote:
> Hi folks, after giving up in frustration I've come back to look at 
> this several months later. To jog memory: I was getting weird lockups 
> trying to get NOS9 working and I was asked to try EOU. EOU Beta 5 
> boots for me, but Beta 6 and later fails to boot. Curtis looked at a 
> video of my boot screen and pointed out Krnp2 did not load and asked 
> if I'd modified the bootfiles (I had not, and confirmed with an md5sum 
> of my disk image). All tests I run on my coco3 for memory, GIME, etc 
> all come back as working fine.
>
>
> So, back to it. I thought maybe if I could add in more debug 
> statements here and there in the boot process, I could track down what 
> was failing and where. To that end, I cloned the latest nos9 code tree 
> from sourceforge (I just used the main branch...is there an EOU branch 
> I'm not finding somewhere?), cross-compiled, it on Ubuntu Linux, and 
> loaded it via drivewire. But lo and behold: everything seems to work 
> fine as long as I stick to access just via DW.
>
> But when I try to do anything involving the cocosdc, it seems to work 
> for a second and then freeze up. For example, running just 'sdc' shows 
> the file listing, but never returns to the prompt.
>
> So...I'm starting to conclude that there is something wrong with my 
> CocoSDC. I've tried different sdcards so I don't think thats it. Its 
> weird that it seems to do everything with standard .dsk images I get 
> from the Color Computer Archive just fine, but only acts weird in 
> NOS9. But the SDC does seem to be the only common factor here.
>
> As such, I have what may be an unusual request: may I borrow someone's 
> known-working CocoSDC to see if the same behavior results? I will pay 
> for shipping both ways.
>
> Also, if anyone has any advice on getting the latest EOU 6.1 working 
> purely via DW and not require a CocoSDC, that could be a good test too.
>
> Thanks!
>
> Don
>
> On 4/30/21 11:58 PM, L. Curtis Boyle wrote:
>> I am sorry, too… I am at a loss at this point. I am by no means a 
>> hardware expert. Hopefully someone who is can help.
>>
>> L. Curtis Boyle
>> curtisboyle at sasktel.net
>>
>>
>>
>>> On Apr 30, 2021, at 9:54 PM, Don Barber <don at dgb3.net> wrote:
>>>
>>> No change in behavior. Appreciate the help.
>>>
>>> Don
>>>
>>> On 4/30/21 10:21 PM, L. Curtis Boyle wrote:
>>>> If you hold down SHIFT when booting, does that make a difference?
>>>>
>>>> L. Curtis Boyle
>>>> curtisboyle at sasktel.net
>>>>
>>>>
>>>>
>>>>> On Apr 30, 2021, at 8:10 PM, Don Barber <don at dgb3.net> wrote:
>>>>>
>>>>> Agree thats the simplest explanation, but I've tried 3-4 different 
>>>>> 512k ram test software packages and they all come back as good.
>>>>>
>>>>> Don
>>>>>
>>>>> On 4/30/21 10:07 PM, L. Curtis Boyle wrote:
>>>>>> Maybe some bad RAM, perhaps? The stock games (for the most part) 
>>>>>> will run in 128K, but EOU (since it preloads some things) 
>>>>>> definitely needs 512K.
>>>>>>
>>>>>> L. Curtis Boyle
>>>>>> curtisboyle at sasktel.net
>>


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