[Coco] NitrOS9 question

[Dave Philipsen]

So just to clarify, in my case it made no difference whether a module inside OS9Boot was expanded legitimately or the OS9Boot file itself was expanded outside of the boundaries of the modules within.  Either way, if the boot file was smaller than $4401 it failed.

Dave

> On Oct 7, 2017, at 6:27 AM, Neal Crook <foofoobedoo at gmail.com> wrote:
> 
> That sounds completely reasonable. Memory is allocated based on the module
> header declaration.. there's not really any way (or reason) to look inside
> the module and determine whether its content is valid/reasonable  (and no
> need for you to zero-out the unused space). In fact you  probably need not
> change the size of the bootfile blob at all.. just the header declaration
> for the last module. Caveat: assuming you have crc checking turned off (as
> it is by default)
> 
> Neal
> 
>> On 7 Oct 2017 10:52, "Dave Philipsen" <dave at davebiz.com> wrote:
>> 
>> Ok, I compiled a minimum headless OS9Boot file that should boot with a
>> shell on T2 as my terminal.  The size of the bootfile is $42F8. When I try
>> to boot with it, as expected,  it fails.  I get the banner text from Init
>> and Sysgo.  Interestingly, sometimes when it boots I also get a string
>> printed to the screen that says, "WHAT?"
>> 
>> Now I use dEd and simply <D>iddle the file length to $4401 and manually
>> clear out the extra data to all zeroes. Voila! NitrOS9 boots and I get the
>> shell prompt on my terminal!  If I diddle it one byte shorter to $4400 it
>> will not boot.  So it apparently matters only that the length of the file
>> is $4401 or longer.
>> 
>> Another interesting point:  If I diddle the file length of OS9Boot even
>> greater to $8000 it still boots but smap reports way less system memory.
>> So that tells me that the system memory allocation is based upon the size
>> of the OS9Boot file, not its actual contents. Apparently no check is made
>> to the contents of the file or whether it contains 'non-modulized' data!
>> 
>> Dave
>> 
>> 
>>> On 10/7/2017 2:48 AM, Neal Crook wrote:
>>> 
>>> My guess is that it will make no difference. If it does, experiment 2 is
>>> to
>>> pad with 0xff. I await the result with interest.
>>> 
>>> Neal.
>>> 
>>> On 7 Oct 2017 08:04, "Dave Philipsen" <dave at davebiz.com> wrote:
>>> 
>>> That would be an interesting experiment. I’ll see if I can try that this
>>>> weekend.
>>>> 
>>>> Dave
>>>> 
>>>> On Oct 6, 2017, at 11:12 PM, Barry Nelson <barry.nelson at amobiledevice.
>>>> com> wrote:
>>>> 
>>>>> What happens if you just pad the end of the OS9Boot file with zeros?
>>>>> 
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