Mercurial > hg > Members > kono > nitros9-code
view level1/atari/modules/clock.asm @ 2624:b8c7b7fbf3c9
Major changes:
o os9defs, rbfdefs, scfdefs now os9.d, rbf.d, and scf.d
o vtiodefs now broken into cocovtio.d (for coco and dragon) and atarivtio.d
o systype now broken into coco.d, dragon.d and atari.d
o all references to the above in other files have changed
| author | Boisy Pitre <boisy.pitre@nuance.com> |
|---|---|
| date | Fri, 24 Feb 2012 08:51:08 -0600 |
| parents | 1df7d248bb24 |
| children |
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******************************************************************** * Clock - NitrOS-9 System Clock for Atari XL/XE * * $Id$ * * Edt/Rev YYYY/MM/DD Modified by * Comment * ------------------------------------------------------------------ * 1 2012/02/22 Boisy G. Pitre * Created nam Clock ttl NitrOS-9 System Clock for Atari XL/XE ifp1 use defsfile endc tylg set Systm+Objct atrv set ReEnt+rev rev set 0 edition set 1 *------------------------------------------------------------ * * Start of module * mod len,name,tylg,atrv,init,0 name fcs "Clock" fcb edition TkPerTS equ TkPerSec/10 ticks per time slice * * Table to set up Service Calls * NewSvc fcb F$Time fdb FTime-*-2 fcb F$VIRQ fdb FVIRQ-*-2 fcb F$STime fdb FSTime-*-2 fcb $80 end of service call installation table *------------------------------------------------------------ * * Handle F$STime system call * * First, copy time packet from user address space to system time * variables, then fall through to code to update RTC. * FSTime equ * ldx R$X,u ldd ,x std <D.Year ldd 2,x std <D.Day ldd 4,x std <D.Min lda #TkPerSec reset to start of second sta <D.Tick ldx <D.Clock2 get entry point to Clock2 clra clear carry jmp $06,x and call SetTime entry point *-------------------------------------------------- * * Clock Initialization * * This vector is called by the kernel to service the first F$STime * call. F$STime is usually called by SysGo (with a dummy argument) * in order to initialize the clock. F$STime is re-vectored to the * service code above to handle future F$STime calls. * * Clock2 fcs "Clock2" init pshs dp,cc save DP and CC clra tfr a,dp set DP to zero leax <Clock2,pcr lda #Sbrtn+Objct os9 F$Link bcc LinkOk jmp >$FFFE level 1: jump to reset vector LinkOk puls cc,dp ; Restore saved dp and cc sty <D.Clock2 save entry point InitCont * Don't need to explicitly read RTC during initialization ldd #59*256+$01 last second and last tick std <D.Sec will prompt RTC read at next time slice ldb #TkPerSec stb <D.TSec set ticks per second ldb #TkPerTS get ticks per time slice stb <D.TSlice set ticks per time slice stb <D.Slice set first time slice leax SvcIRQ,pcr set NMI handler stx <D.NMI leay NewSvc,pcr insert syscalls os9 F$SSvc * Call Clock2 init routine ldy <D.Clock2 get entry point to Clock2 jsr ,y call init entry point of Clock2 * Tell ANTIC to assert NMI on Vertical Blank lda #$40 sta $D40E enable VBlank NMI InitRts rts * * Clock IRQ Entry Point * * Called once every 16.667 milliseconds SvcIRQ clra tfr a,dp set direct page to zero sta $D40F clear NMI interrupt * tst PIA0Base+3 get hw byte * bmi L0032 branch if sync flag on * jmp [>D.SvcIRQ] else service other possible IRQ L0032 dec <D.Tick decrement tick counter bne L007F go around if not zero ldb <D.Sec get minutes/seconds * Seconds increment incb increment seconds cmpb #60 full minute? bcs L0079 nope... * * Call GetTime entry point in Clock2 * ldx <D.Clock2 get entry point to Clock2 jsr $03,x call GetTime entry point fcb $8C skip next 2 bytes L0079 stb <D.Sec update sec L007B lda <D.TSec get ticks per second value sta <D.Tick and repopulate tick decrement counter L007F clra clear A pshs a and save it on the stack ldy <D.CLTb get pointer to VIRQ Polling Entries bra L009E go to the processing portion of the loop L0087 ldd Vi.Cnt,x get count down counter subd #$0001 subtract tick count bne L009C branch if not at terminal count ($0000) lda #$01 sta ,s set flag on stack to 1 lda Vi.Stat,x get status byte beq DelEntry branch if zero (one shot, so delete) L0096 ora #Vi.IFlag set interrupted flag sta Vi.Stat,x save in packet ldd Vi.Rst,x get reset count L009C std Vi.Cnt,x save tick count back L009E ldx ,y++ get two bytes at Y bne L0087 if not zero, branch lda ,s+ else get byte off stack beq GoAltIRQ branch if zero ldx <D.Proc else get pointer to current process descriptor beq L00AE branch if none tst P$State,x test process' state bpl UsrPoll branch if system state not set L00AE jsr [>D.Poll] poll ISRs bcc L00AE keep polling until carry set GoAltIRQ jmp [>D.AltIRQ] jump into an alternate IRQ if available DelEntry bsr DelVIRQ delete the VIRQ entry bra L0096 UsrPoll leay >up@,pcr point to routine to execute jmp [>D.URtoSs] User to System up@ jsr [>D.Poll] call polling routine bcc up@ keep polling until carry set ldx <D.Proc get current process descriptor ldb P$State,x and its state andb #^SysState turn off sysstate bit stb P$State,x save new state ldd <P$SWI2,x std <D.SWI2 ldd <D.UsrIRQ std <D.SvcIRQ bra GoAltIRQ DelVIRQ pshs y,x save off Y,X dl@ ldx ,y++ get next entry stx -$04,y move up bne dl@ continue until all are moved puls y,x restore leay -2,y move back 2 from Y (points to last entry) rts return * Install or Remove VIRQ Entry FVIRQ pshs cc orcc #IntMasks mask all interrupts ldy <D.CLTb get pointer to VIRQ polling table ldx <D.Init get pointer to init module ldb PollCnt,x get poll count ldx R$X,u get pointer to caller's X beq L0118 branch if removing tst ,y entry available? beq L010C subb #$02 lslb leay b,y tst ,y bne PTblFul polling table full L0106 tst ,--y beq L0106 leay $02,y L010C ldx R$Y,u stx ,y ldy R$D,u sty ,x bra L0124 L0118 leax R$Y,u X = caller's Y L011A tst ,y end of VIRQ table beq L0124 branch if so cmpx ,y++ else compare to current VIRQ entry and inc Y bne L011A continue searching if not matched bsr DelVIRQ else delete entry L0124 puls cc clrb rts PTblFul puls cc comb ldb #E$Poll rts * F$Time system call code FTime ldx R$X,u ldd <D.Year std ,x ldd <D.Day std 2,x ldd <D.Min std 4,x clrb rts emod len equ * end