[Coco] How to trick Disk BASIC?, or Drivewire sans disk controller...

[Robert Gault]

Darren A wrote:
> On 2/15/10, Arthur Flexser wrote:
>>
>> The CART autostart jumps to $C000 after checking that the first two bytes
>> of the cartridge ROM are not ASCII "DK", which would indicate a disk
>> controller.
>> If "DK" is found, the jump is to $C002.  But, I really don't think the
>> two-byte difference in addresses accounts for your crash.
>
> The CART auto-start happens very early in the initialization sequence,
> just after Color Basic has configured the PIAs and SAM.
>
> Disk Basic doesn't use auto-start, because it requires that Color and
> Extended Basic perform nearly all of their initialization tasks before
> handing off to Disk Basic.  The check for "DK" is done by the Extended
> Basic ROM, and this is why Disk Basic won't start if you only have
> Color Basic in the CoCo.
>
> Darren
>

Indeed! It gets worse with a Coco3 because if you immediately jump to the CART, 
Super Extended Basic won't be initialized.