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cc65/libsrc/apple2/getres.s

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Added clock_getres() / clock_settime() for the Apple II. The situation on the Apple II is rather special: There are several types of RTCs. It's not desirable to have specific code for all of them. As the OS supports file timestamps RTC owners usually use OS drivers for their RTC. Those drivers read the RTC and write the result in a "date/time location" in RAM. The OS reads the date/time from the RAM location. If there's no RTC the RAM location keeps containing zeros. The OS uses those zeros as timestamps and the files show up in a directory as "<NO DATE>". There's no common interface to set RTCs so if an RTC _IS_ present there's just nothing to do. However, if there's _NO_ RTC present the user might very well be interest to "manually" set the RAM location in order to have timestamps. But he surely doesn't want to manually set the RAM location over an over again. Rather he wants to set it just once after booting the OS. From that perspective it makes most sense to not set both the date and the time but rather only set the date and have the time just stay zero. Then files show up in a directory as "DD-MON-YY 0:00". So clock_settime() checks if the current time equals 0:00. If it does _NOT_ then an RTC is supposed to be active and clock_settime() fails with ERANGE. Otherwise clock_settime() ignores sets the date - and completely ignores the time provided as parameter. clock_getres() too checks if the current time equals 0:00. If it does _NOT_ then an RTC is supposed to be active and clock_getres() returns a time resolution of one minute. Otherwise clock_getres() presumes that the only one who sets the RAM location is clock_settime() and therefore returns a time resolution of one day.
2018-08-15 19:34:35 +00:00
;
; Oliver Schmidt, 15.08.2018
;
Atari: implement clock_getres()
2018-09-27 18:22:21 +00:00
; int __fastcall__ clock_getres (clockid_t clk_id, struct timespec *res);
Added clock_getres() / clock_settime() for the Apple II. The situation on the Apple II is rather special: There are several types of RTCs. It's not desirable to have specific code for all of them. As the OS supports file timestamps RTC owners usually use OS drivers for their RTC. Those drivers read the RTC and write the result in a "date/time location" in RAM. The OS reads the date/time from the RAM location. If there's no RTC the RAM location keeps containing zeros. The OS uses those zeros as timestamps and the files show up in a directory as "<NO DATE>". There's no common interface to set RTCs so if an RTC _IS_ present there's just nothing to do. However, if there's _NO_ RTC present the user might very well be interest to "manually" set the RAM location in order to have timestamps. But he surely doesn't want to manually set the RAM location over an over again. Rather he wants to set it just once after booting the OS. From that perspective it makes most sense to not set both the date and the time but rather only set the date and have the time just stay zero. Then files show up in a directory as "DD-MON-YY 0:00". So clock_settime() checks if the current time equals 0:00. If it does _NOT_ then an RTC is supposed to be active and clock_settime() fails with ERANGE. Otherwise clock_settime() ignores sets the date - and completely ignores the time provided as parameter. clock_getres() too checks if the current time equals 0:00. If it does _NOT_ then an RTC is supposed to be active and clock_getres() returns a time resolution of one minute. Otherwise clock_getres() presumes that the only one who sets the RAM location is clock_settime() and therefore returns a time resolution of one day.
2018-08-15 19:34:35 +00:00
;
.import __dos_type
.import incsp1, return0
.include "time.inc"
.include "zeropage.inc"
.include "errno.inc"
.include "mli.inc"
_clock_getres:
sta ptr1
stx ptr1+1
; Cleanup stack
jsr incsp1
; Check for ProDOS 8
lda __dos_type
beq enosys
; Presume day resolution
ldx #<day_res
ldy #>day_res
Use MACHID to check for realtime clock. There's no need to do guesswork to know if a realtime clock is present/active.
2019-09-10 07:49:06 +00:00
; Check for realtme clock
lda MACHID
lsr a
bcc :+
Added clock_getres() / clock_settime() for the Apple II. The situation on the Apple II is rather special: There are several types of RTCs. It's not desirable to have specific code for all of them. As the OS supports file timestamps RTC owners usually use OS drivers for their RTC. Those drivers read the RTC and write the result in a "date/time location" in RAM. The OS reads the date/time from the RAM location. If there's no RTC the RAM location keeps containing zeros. The OS uses those zeros as timestamps and the files show up in a directory as "<NO DATE>". There's no common interface to set RTCs so if an RTC _IS_ present there's just nothing to do. However, if there's _NO_ RTC present the user might very well be interest to "manually" set the RAM location in order to have timestamps. But he surely doesn't want to manually set the RAM location over an over again. Rather he wants to set it just once after booting the OS. From that perspective it makes most sense to not set both the date and the time but rather only set the date and have the time just stay zero. Then files show up in a directory as "DD-MON-YY 0:00". So clock_settime() checks if the current time equals 0:00. If it does _NOT_ then an RTC is supposed to be active and clock_settime() fails with ERANGE. Otherwise clock_settime() ignores sets the date - and completely ignores the time provided as parameter. clock_getres() too checks if the current time equals 0:00. If it does _NOT_ then an RTC is supposed to be active and clock_getres() returns a time resolution of one minute. Otherwise clock_getres() presumes that the only one who sets the RAM location is clock_settime() and therefore returns a time resolution of one day.
2018-08-15 19:34:35 +00:00
; Switch to minute resolution
ldx #<min_res
ldy #>min_res
; Copy timespec
: stx ptr2
sty ptr2+1
ldy #.sizeof(timespec)-1
: lda (ptr2),y
sta (ptr1),y
dey
bpl :-
; Return success
jmp return0
; Load errno code
enosys: lda #ENOSYS
; Set __errno
jmp __directerrno
.rodata
min_res:.dword 60
.dword 0
day_res:.dword 60 * 60 * 24
.dword 0
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