[Coco] a not very important drivewire question

William Astle lost at l-w.ca
Thu Jul 17 01:50:39 EDT 2014


On 14-07-16 10:35 PM, Aaron Wolfe wrote:
> Fwiw, there are printer operations built into the protocol and an os9 /p
> module that uses them so programs can print without needing modification.
> I don't know if hdbdos makes print #-2 work in basic, but it could probably
> be done fairly easily if not.

If there was ROM space, it could be anyway.

> Is there a need for any check on the drive number?  It appears to be stored
> in the B register so there is no possible value that isn't a valid drive.  ?

For drivewire, the test is pointless. Other HDBDOS flavours do have real 
limits, though. It's probably an artifact of that. The check could 
probably be wrapped in a conditional so it doesn't apply in the 
drivewire case.

>   On Jul 17, 2014 12:28 AM, "Robert Hermanek" <rhermanek at centurytel.net>
> wrote:
>
>> No, I think we're just dealing with assembler constants here... so when
>> the comparison is with MAXDN-1 at assembly time, we're dealing with 255-1 =
>> 254.  I guess the question is, why is the "-1" there? Maybe MAXDN = 255 is
>> fine, and the -1 should disappear... anyway, as Robert G mentioned, would
>> be curious if others can do DRIVE #255, keeping in mind the "#" is
>> important, referring to the device #, not the disk number.
>>
>> But, as I mentioned, not that important... I can scrape by with 0-254, so
>> 255 devices X 256 disks per device = mega storage :) Was just curious.  I
>> have a home-brew drivewire server, and I was setting it up to take any DSKO
>> activity to Drive # 255, disk 255, track 34 sector 18, to be considered
>> output to a virtual printer, allowing coco programs to easily pass data to
>> a DWP 220 I've got sitting here attached to my PC... that's why it came up.
>>
>> -RobertH
>>
>>
>> On 7/16/2014 10:01 PM, Gene Heskett wrote:
>>
>>> the value of MAXDN for DW be changed to 256.
>>>>>
>>>>> Robert
>>>>
>>> Whats the data size of MAXDN? 256 is a 2 byte value, as its 0x0100, and
>>> needs an int to store it.
>>>
>>
>>
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>>
>



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