[Coco] assembler directive

L. Curtis Boyle curtisboyle at sasktel.net
Thu Oct 5 17:12:39 EDT 2017


You are correct - The first F$STime call inits the clock IRQ’s, from what I remember. And there is a chain of modules that it goes through on those IRQ’s, depending.

L. Curtis Boyle
curtisboyle at sasktel.net



> On Oct 5, 2017, at 3:09 PM, Dave Philipsen <dave at davebiz.com> wrote:
> 
> Thanks, Robert.  I had already replaced the dtb with fcb however I was unaware that the base year was 1900 so I corrected that.  It seems this call to F$STime in the sysgo program is a necessary initial call that gets the multitasking and clock interrupts initialized.  Without it I cannot get a shell.
> 
> Dave
> 
> On 10/5/2017 3:30 PM, Robert Gault wrote:
>> Dave Philipsen wrote:
>>> Thanks, Robert.  I’m not actually using LWASM else it would have been easy to figure it out. I am assembling the source for the modules with the native OS9 assembler which, obviously, does not recognize the directive. If there were a version of LWASM for OS9 I would consider using it.
>>> 
>>> I’m very familiar with using a cross assembler on another system to generate code and then uploading the code to the target system for testing.  Usually this is done because the target system does not have the resources to run an assembler. But in this case I have a full-blown operating system and an assembler and enough speed to do it right on the same box.  I also realize that, for the CoCo, this could be done fairly quickly with an emulator on a PC.  However, to my knowledge, neither the CoCo3FPGA nor my non-CoCo 6809 system are emulated so that’s another reason I’m converting this stuff over.
>>> 
>>> Dave
>>> 
>> 
>> Ok, just remove the dtb and replace it with an fcb similar to that found in dwio.asm
>> * Default time packet
>> DefTime        fcb       109,12,31,23,59,59
>> 
>> The above is used with the call F$STime so the values are year, month, day, hours, minutes, seconds.
>> 
>> I don't remember but think year starts at 1900 so 109+1900=2009 and might be when dwio.asm was written. The value I get by assembling the SourceForge code does seem consistent with my PC clock as the year is $75=117 117+1900=2017 .
>> 
>> Robert
>> 
>> 
> 
> 
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