95 lines
2.5 KiB
NASM
95 lines
2.5 KiB
NASM
/*------------------------------------------------------------------------
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FILE : start.asm |
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DATE : Wed, Aug 25, 2010 |
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DESCRIPTION : Reset Program |
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CPU TYPE : Other |
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This file is generated by KPIT GNU Project Generator (Ver.4.5). |
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------------------------------------------------------------------------*/
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/*Start.asm*/
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.list
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.section .text
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.global _start /*global Start routine */
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#ifdef CPPAPP
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___dso_handle:
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.global ___dso_handle
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#endif
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.extern _hw_initialise /*external Sub-routine to initialise Hardware*/
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.extern _data
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.extern _mdata
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.extern _ebss
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.extern _bss
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.extern _edata
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.extern _main
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.extern _ustack
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.extern _istack
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.extern _rvectors
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#if DEBUG
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.extern _exit
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#endif
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_start:
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/* initialise user stack pointer */
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mvtc #_ustack,USP
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/* initialise interrupt stack pointer */
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mvtc #_istack,ISP
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/* setup intb */
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mvtc #_rvectors_start, intb /* INTERRUPT VECTOR ADDRESS definition */
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/* setup FPSW */
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mvtc #100h, fpsw
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/* load data section from ROM to RAM */
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mov #_mdata,r2 /* src ROM address of data section in R2 */
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mov #_data,r1 /* dest start RAM address of data section in R1 */
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mov #_edata,r3 /* end RAM address of data section in R3 */
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sub r1,r3 /* size of data section in R3 (R3=R3-R1) */
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smovf /* block copy R3 bytes from R2 to R1 */
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/* bss initialisation : zero out bss */
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mov #00h,r2 /* load R2 reg with zero */
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mov #_ebss, r3 /* store the end address of bss in R3 */
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mov #_bss, r1 /* store the start address of bss in R1 */
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sub r1,r3 /* size of bss section in R3 (R3=R3-R1) */
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sstr.b
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/* call the hardware initialiser */
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bsr.a _hw_initialise
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nop
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/* setup PSW */
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// mvtc #10000h, psw /* Set Ubit & Ibit for PSW */
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/* change PSW PM to user-mode */
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// MVFC PSW,R1
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// OR #00100000h,R1
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// PUSH.L R1
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// MVFC PC,R1
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// ADD #10,R1
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// PUSH.L R1
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// RTE
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// NOP
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// NOP
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/* start user program */
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bsr.a _main
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/* call to exit*/
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_exit:
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bsr.a _exit
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.end
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