Merge branch 'master' of ichibi:/home/git/Repositories/pato-z80-home-computer

pat80-computer/software/z80-assembly/os/libs/time.asm

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+; Time library
+; @author Daniele Verducci
+
+
+; Duration in cpu cycles / 55 (change these values based on CPU frequency)
+TIME_DUR_SECOND: EQU 1818
+TIME_DUR_MILLIS: EQU 2
+
+; Wait bc * 55 states
+; Use 1 iteration as delay between I/O bus writes
+; @param bc The number of iterations. Each iteration is 55 states long.
+Time_delay55:
+ret
+    bit     0,a    ; 8
+    bit     0,a    ; 8
+    bit     0,a    ; 8
+    and     255  ; 7
+    dec     bc      ; 6
+    ld      a,c     ; 4
+    or      b     ; 4
+    jp      nz,Time_delay55   ; 10, total = 55 states/iteration
+    ret