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;;delay_us

#include <pkgconf/hal.h>        

#include <cyg/hal/arch.inc>     
#include <cyg/hal/basetype.h>
#include <cyg/hal/mod_regs_tmr.h>

#define DELAY_COUNT (CYGHWR_HAL_H8300_PROCESSOR_SPEED/1000000)/8*25
        
//      .file   "delay_us.S"
        .h8300h
        .text

        .global CYG_LABEL_DEFN(hal_delay_us)
CYG_LABEL_DEFN(hal_delay_us):
        mov.b   #0,r1l
        mov.b   r1l,@CYGARC_8TCNT2:8
        mov.b   #1,r1l
        mov.b   r1l,@CYGARC_8TCR2:8
        mov.b   #0,r2h
        sub.w   e1,e1
1:
        mov.l   er0,er0
        ble     6f
2:      
        cmp.w   #DELAY_COUNT,e1
        bgt     5f
        mov.b   #0,r1h
        mov.b   @CYGARC_8TCNT2:8,r2l
3:      
        mov.b   @CYGARC_8TCNT2:8,r1l
        cmp.b   r1l,r2l
        beq     3b
        bcs     4f
        inc.b   r1h
4:
        sub.w   r2,r1
        add.w   r1,e1
        bra     2b
5:
        mov.w   e1,r1
        mov.b   #DELAY_COUNT,r2l
        divxs   r2l,r1
        sub.l   er2,er2
        mov.b   r1l,r2l
        sub.w   r2,e1
        dec.l   #1,er0
        bra     1b
6:
        mov.b   #0,r0l
        mov.b   r0l,@CYGARC_8TCR2
        rts