added c64.RDTIM16() utility routine to just get the lower 16 bits of the jiffy clock

compiler/res/prog8lib/c64/syslib.p8

@@ -245,6 +245,20 @@ asmsub STOP2() -> ubyte @A  {
     }}
 }
 
+asmsub RDTIM16() -> uword @AY {
+    ; --  like RDTIM() but only returning the lower 16 bits for convenience
+    %asm {{
+        stx  P8ZP_SCRATCH_REG
+        jsr  c64.RDTIM
+        pha
+        txa
+        tay
+        pla
+        ldx  P8ZP_SCRATCH_REG
+        rts
+    }}
+}
+
 
 
 ; ---- C64 specific system utility routines: ----
@@ -291,18 +305,9 @@ asmsub  reset_system()  {
 }
 
 sub wait(uword jiffies) {
-    uword current_time = 0
+    c64.SETTIM(0,0,0)           ; TODO do the wait without resetting the jiffy clock
-    c64.SETTIM(0,0,0)
+    while c64.RDTIM16() < jiffies {
-
+        ; wait till the time catches up
-    while current_time < jiffies {
-        ; read clock
-        %asm {{
-            stx  P8ZP_SCRATCH_REG
-            jsr  c64.RDTIM
-            sta  current_time
-            stx  current_time+1
-            ldx  P8ZP_SCRATCH_REG
-        }}
     }
 }
 

compiler/res/prog8lib/cx16/syslib.p8

@@ -73,6 +73,22 @@ asmsub STOP2() -> ubyte @A  {
     }}
 }
 
+
+asmsub RDTIM16() -> uword @AY {
+    ; --  like RDTIM() but only returning the lower 16 bits for convenience
+    %asm {{
+        phx
+        jsr  c64.RDTIM
+        pha
+        txa
+        tay
+        pla
+        plx
+        rts
+    }}
+}
+
+
 }
 
 cx16 {
@@ -415,18 +431,9 @@ _loop       ldy  #0
 
 
 sub wait(uword jiffies) {
-    uword current_time = 0
+    c64.SETTIM(0,0,0)           ; TODO do the wait without resetting the jiffy clock
-    c64.SETTIM(0,0,0)
+    while c64.RDTIM16() < jiffies {
-
+        ; wait till the time catches up
-    while current_time < jiffies {
-        ; read clock
-        %asm {{
-            phx
-            jsr  c64.RDTIM
-            sta  current_time
-            stx  current_time+1
-            plx
-        }}
     }
 }
 

docs/source/todo.rst

@@ -2,8 +2,9 @@
 TODO
 ====
 
-- add syslib.rdtim16() function to wrap the RDTIM to read only the lower 16 bits of the jiffyclock - fix examples.
 - move all str* builtin functions to a str library module
+- make the syslib.wait() functions not reset the jiffy clock to 0
+- move wait() and others?  to sys.*  block to unify them from c64.* and cx16.* separation
 - detect variables that are written but never read - mark those as unused too and remove them, such as uword unused = memory("unused222", 20) - also remove the memory slab allocation
 - hoist all variable declarations up to the subroutine scope *before* even the constant folding takes place (to avoid undefined symbol errors when referring to a variable from another nested scope in the subroutine)
 - make it possible to use cpu opcodes such as 'nop' as variable names by prefixing all asm vars with something such as '_'

examples/assembler/assem.p8

@@ -42,7 +42,6 @@ main {
         txt.print_uw(amount)
         txt.print(" mnemonics")
 
-        uword current_time = 0
         c64.SETTIM(0,0,0)
 
         uword total = 0
@@ -58,16 +57,7 @@ main {
             }
         }
 
-        ; read clock back
+        uword current_time = c64.RDTIM16()
-        %asm {{
-            phx
-            jsr  c64.RDTIM
-            sta  current_time
-            stx  current_time+1
-            plx
-        }}
-
-
         txt.print("\nDone.\nValid: ")
         txt.print_uw(valid)
         txt.print("\ninvalid: ")

examples/balls.p8

@@ -85,15 +85,7 @@ main {
             ;txt.print_uw(frame)
         }
 
-        ; read clock
+        uword jiffies = c64.RDTIM16()
-        uword jiffies
-        %asm {{
-            stx  P8ZP_SCRATCH_REG
-            jsr  c64.RDTIM
-            sta  jiffies
-            stx  jiffies+1
-            ldx  P8ZP_SCRATCH_REG
-        }}
         txt.print("\nbenchmark: ")
         txt.print_uw(jiffies)
         txt.print(" jiffies for 1000 frames.\n")

examples/cube3d-float.p8

@@ -19,9 +19,10 @@ main {
 
     sub start()  {
         float time=0.0
-        ubyte timer_jiffies
 
         repeat {
+            c64.SETTIM(0,0,0)
+
             rotate_vertices(time)
             txt.clear_screenchars(' ')
             draw_edges()
@@ -30,17 +31,11 @@ main {
             txt.plot(0,0)
             txt.print("3d cube! floats. ")
 
-            %asm {{
+
-                stx  P8ZP_SCRATCH_REG
+            ubyte jiffies = lsb(c64.RDTIM16())
-                jsr  c64.RDTIM      ; A/X/Y
+            txt.print_ub(jiffies)
-                sta  timer_jiffies
-                lda  #0
-                jsr  c64.SETTIM
-                ldx  P8ZP_SCRATCH_REG
-            }}
-            txt.print_ub(timer_jiffies)
             txt.print(" jiffies/fr = ")
-            txt.print_ub(60/timer_jiffies)
+            txt.print_ub(60/jiffies)
             txt.print(" fps")
 
             ;test_stack.test()

examples/cube3d-gfx.p8

@@ -37,25 +37,12 @@ main {
             angley+=217
             anglez+=452
 
-            wait_a_little_bit()
+            c64.wait(2)
 
             ; test_stack.test()
         }
     }
 
-    sub wait_a_little_bit() {
-        %asm {{
-            stx  P8ZP_SCRATCH_REG
-            lda  #0
-            jsr  c64.SETTIM
--           jsr  c64.RDTIM
-            cmp  #1
-            bne  -
-            ldx  P8ZP_SCRATCH_REG
-            rts
-        }}
-    }
-
     sub rotate_vertices(ubyte ax, ubyte ay, ubyte az) {
         ; rotate around origin (0,0,0)
 

examples/hello.p8

@@ -1,57 +0,0 @@
-%import syslib
-%import textio
-%import floats
-%zeropage basicsafe
-
-; Note: this program is compatible with C64 and CX16.
-
-main {
-
-    sub start() {
-
-        txt.lowercase()
-
-        ; use optimized routine to write text
-        txt.print("Hello!\n")
-
-        ; use iteration to write text
-        str question = "How are you?\n"
-        ubyte char
-        for char in question
-            txt.chrout(char)
-
-        ; use indexed loop to write characters
-        str bye = "Goodbye!\n"
-        for char in 0 to len(bye)-1
-            txt.chrout(bye[char])
-
-        ubyte time_lo
-        ubyte time_mid
-        ubyte time_hi
-
-        %asm {{
-            stx  P8ZP_SCRATCH_REG
-            jsr  c64.RDTIM      ; A/X/Y
-            sta  time_lo
-            stx  time_mid
-            sty  time_hi
-            ldx  P8ZP_SCRATCH_REG
-        }}
-
-        float clock_seconds = ((mkword(time_mid, time_lo) as float) + (time_hi as float)*65536.0) / 60
-        float hours = floor(clock_seconds / 3600)
-        clock_seconds -= hours*3600
-        float minutes = floor(clock_seconds / 60)
-        clock_seconds = floor(clock_seconds - minutes * 60.0)
-
-        txt.print("system time (jiffy clock) is ")
-        floats.print_f(hours)
-        txt.chrout(':')
-        floats.print_f(minutes)
-        txt.chrout(':')
-        floats.print_f(clock_seconds)
-        txt.chrout('\n')
-
-        txt.print("bye!\n")
-    }
-}

examples/mandelbrot.p8

@@ -40,20 +40,7 @@ main {
             }
         }
 
-        ubyte time_lo
+        float duration = (c64.RDTIM16() as float) / 60
-        ubyte time_mid
-        ubyte time_hi
-
-        %asm {{
-            stx  P8ZP_SCRATCH_REG
-            jsr  c64.RDTIM      ; A/X/Y
-            sta  time_lo
-            stx  time_mid
-            sty  time_hi
-            ldx  P8ZP_SCRATCH_REG
-        }}
-
-        float duration = ((mkword(time_mid, time_lo) as float) + (time_hi as float)*65536.0) / 60
         txt.plot(0, 21)
         txt.print("finished in ")
         floats.print_f(duration)

examples/test.p8

@@ -8,34 +8,15 @@ main {
 
     sub start () {
         uword current_time
-        uword secs
-        const uword test_value = 1261
 
-        current_time = test_value
+        repeat {
-        secs = current_time / 60
+            current_time = c64.RDTIM16()
-        current_time = (current_time - secs*60)*1000/60
+            txt.print_uw(current_time)
-        txt.print_uw(secs)
+            txt.chrout('\n')
-        txt.chrout('.')
+            repeat 20000 {
-        if current_time<10
+                current_time++
-            txt.chrout('0')
+            }
-        if current_time<100
+        }
-            txt.chrout('0')
-        txt.print_uw(current_time)
-        txt.chrout('\n')
-
-        current_time = test_value
-        secs = current_time / 60
-        current_time = current_time - secs*60
-        current_time *= 1000
-        current_time /= 60
-        txt.print_uw(secs)
-        txt.chrout('.')
-        if current_time<10
-            txt.chrout('0')
-        if current_time<100
-            txt.chrout('0')
-        txt.print_uw(current_time)
-        txt.chrout('\n')
 
 
 ;        found = strfind("irmen de jong", ' ')