Difference between revisions of "OSWORD &0E"

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(Added subfunction 3.)
(Added subcode 3,4 and implementation details.)
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[[Category:OSWORD]]
 
[[Category:OSWORD]]
−
OSWORD &0E (14 ) - Reads CMOS clock
+
OSWORD &0E (14) - Reads CMOS clock
  
 
  On entry:
 
  On entry:
−
   XY+0=function code
+
   XY?0=function code
  
 
  0 - Return clock value as string
 
  0 - Return clock value as string
 
   On exit:
 
   On exit:
 
   XY+0..23=CR-terminated string in form
 
   XY+0..23=CR-terminated string in form
−
   "Day,DD Mon Year.HH:MM:SS".
+
   "Day,DD Mon Year.HH:MM:SS"
  
 
  1 - Return BCD clock value.
 
  1 - Return BCD clock value.
Line 15: Line 15:
 
   XY?1=month (&01-&12)
 
   XY?1=month (&01-&12)
 
   XY?2=date (&01-&31)
 
   XY?2=date (&01-&31)
−
   XY?3=day of week (&01-&07, Sun-Sat)
+
   XY?3=day of week (&01-&07, Sun-Sat or &00, not returned)
 
   XY?4=hours (&00-&23)
 
   XY?4=hours (&00-&23)
 
   XY?5=minutes (&00-&59)
 
   XY?5=minutes (&00-&59)
−
   XY?6=seconds (&00-&59).
+
   XY?6=seconds (&00-&59)
 
    
 
    
 
   A year value of &80-&99 represents 1980-1999, a value of
 
   A year value of &80-&99 represents 1980-1999, a value of
Line 32: Line 32:
 
   On exit:
 
   On exit:
 
   XY?0..4=number of centiseconds since 00:00:00 01-Jan-1900
 
   XY?0..4=number of centiseconds since 00:00:00 01-Jan-1900
 +
 +
3 - Return clock value as string from file server (ANFS 4.2x)
 +
  On exit:
 +
  XY+0..23=CR-terminated string in form
 +
  "Day,DD Mon Year.HH:MM:SS"
 +
 +
4 - Return BCD clock value from file server (ANFS).
 +
  On exit:
 +
  XY?0=year (&00-&99)
 +
  XY?1=month (&01-&12)
 +
  XY?2=date (&01-&31)
 +
  XY?3=day of week (&00, not returned)
 +
  XY?4=hours (&00-&23)
 +
  XY?5=minutes (&00-&59)
 +
  XY?6=seconds (&00-&59)
 +
 
 +
  A year value of &80-&99 represents 1980-1999, a value of
 +
  &00-&79 represents 2000-2079.
 +
 +
? - Return BCD time/date/temperature
 +
 +
? - Return time/date/temperature string
 +
 +
==Implementation==
 +
On a system without a Real Time Clock, the MOS passes OSWORD 14 to sideways
 +
ROMs for support.
 +
 +
===ANFS===
 +
Master ANFS 4.2x implements subcalls 0,1,3,4 and calls OSWORD 14,2 to
 +
convert the result of subcall 0 and 3 to a string. BBC ANFS 4.0x and 4.1x
 +
only implements OSWORD 14,4.
 +
 +
The ANFS implementation fails in a predictable manner with dates after
 +
1996. The returned date is ((year-1981) DIV 16)*16+date and the returned
 +
year is (year-1981) AND 15. The date can be repaired across the whole date
 +
range with:
 +
 +
  date =BCDtoBIN(returned_date) AND 31
 +
  month=BCDtoBIN(returned_month)
 +
  year =(BCDtoBIN(returned_date) AND &E0) DIV 2 + BCDtoBIN(returned-year) + 1900
 +
 +
===SoftRTC===
 +
The SoftRTC module (included in HADFS) implements subcalls 0,1,2 with the
 +
date set with *SETDATE and the time being calculated from TIME.
  
 
==See Also==
 
==See Also==
Line 38: Line 82:
  
 
[[User:Jgharston|Jgharston]] 12:56, 26 May 2009 (UTC)
 
[[User:Jgharston|Jgharston]] 12:56, 26 May 2009 (UTC)
 +
[[User:Jgharston|Jgharston]] ([[User talk:Jgharston|talk]]) 14:36, 23 January 2019 (CET)

Revision as of 14:36, 23 January 2019

OSWORD &0E (14) - Reads CMOS clock 

On entry:
 XY?0=function code

0 - Return clock value as string
 On exit:
  XY+0..23=CR-terminated string in form
  "Day,DD Mon Year.HH:MM:SS"

1 - Return BCD clock value.
 On exit:
  XY?0=year (&00-&99)
  XY?1=month (&01-&12)
  XY?2=date (&01-&31)
  XY?3=day of week (&01-&07, Sun-Sat or &00, not returned)
  XY?4=hours (&00-&23)
  XY?5=minutes (&00-&59)
  XY?6=seconds (&00-&59)
 
 A year value of &80-&99 represents 1980-1999, a value of
 &00-&79 represents 2000-2079.

2 - Convert BCD to string.
 On entry:
  XY+1..7=BCD value as with subfunction 1
 On exit:
  XY+1..25=CR-terminated string as with subfunction 0

3 - Return 5-byte centisecond clock value (where supported)
 On exit:
  XY?0..4=number of centiseconds since 00:00:00 01-Jan-1900

3 - Return clock value as string from file server (ANFS 4.2x)
 On exit:
  XY+0..23=CR-terminated string in form
  "Day,DD Mon Year.HH:MM:SS"

4 - Return BCD clock value from file server (ANFS).
 On exit:
  XY?0=year (&00-&99)
  XY?1=month (&01-&12)
  XY?2=date (&01-&31)
  XY?3=day of week (&00, not returned)
  XY?4=hours (&00-&23)
  XY?5=minutes (&00-&59)
  XY?6=seconds (&00-&59)
 
 A year value of &80-&99 represents 1980-1999, a value of
 &00-&79 represents 2000-2079.

? - Return BCD time/date/temperature

? - Return time/date/temperature string

Implementation

On a system without a Real Time Clock, the MOS passes OSWORD 14 to sideways ROMs for support.

ANFS

Master ANFS 4.2x implements subcalls 0,1,3,4 and calls OSWORD 14,2 to convert the result of subcall 0 and 3 to a string. BBC ANFS 4.0x and 4.1x only implements OSWORD 14,4.

The ANFS implementation fails in a predictable manner with dates after 1996. The returned date is ((year-1981) DIV 16)*16+date and the returned year is (year-1981) AND 15. The date can be repaired across the whole date range with: 

 date =BCDtoBIN(returned_date) AND 31
 month=BCDtoBIN(returned_month)
 year =(BCDtoBIN(returned_date) AND &E0) DIV 2 + BCDtoBIN(returned-year) + 1900

SoftRTC

The SoftRTC module (included in HADFS) implements subcalls 0,1,2 with the date set with *SETDATE and the time being calculated from TIME.

See Also

Jgharston 12:56, 26 May 2009 (UTC) Jgharston (talk) 14:36, 23 January 2019 (CET)

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