URL https://opencores.org/ocsvn/plasma/plasma/trunk

Subversion Repositories plasma

[/] [plasma/] [trunk/] [tools/] [boot.asm] - Diff between revs 47 and 110

Rev 47	Rev 110
Line 14...	Line 14...
`.globl entry`	`.globl entry`
`.ent entry`	`.ent entry`
`entry:`	`entry:`
`.set noreorder`	`.set noreorder`

`#These nine instructions must be the first instructions`	`#These eight instructions must be the first instructions.`
`#convert.exe will correctly initialize $gp`	`#convert.exe will correctly initialize $gp`
`lui $gp,0`	`lui $gp,0`
`ori $gp,$gp,0`	`ori $gp,$gp,0`
`#convert.exe will set $4=.sbss_start $5=.bss_end`	`#convert.exe will set $4=.sbss_start $5=.bss_end`
`ori $4,$0,0`	`lui $4,0`
`ori $5,$0,0`	`ori $4,$4,0`
`ori $sp,$0,0xfff0 #initialize stack pointer`	`lui $5,0`
	`ori $5,$5,0`
	`lui $sp,0`
	`ori $sp,$sp,0xfff0 #initialize stack pointer`
`$BSS_CLEAR:`	`$BSS_CLEAR:`
`sw $0,0($4)`	`sw $0,0($4)`
`slt $3,$4,$5`	`slt $3,$4,$5`
`bnez $3,$BSS_CLEAR`	`bnez $3,$BSS_CLEAR`
`addiu $4,$4,4`	`addiu $4,$4,4`
Line 33...	Line 36...
`jal main2`	`jal main2`
`nop`	`nop`
`$L1:`	`$L1:`
`j $L1`	`j $L1`

`#address 0x30`	`#address 0x3c`
`interrupt_service_routine:`	`interrupt_service_routine:`
`#registers $26 and $27 are reserved for the OS`	`#registers $26 and $27 are reserved for the OS`
`ori $26,$0,0xffff`	`ori $26,$0,0xffff`
`ori $27,$0,46`	`ori $27,$0,46`
`sb $27,0($26) #echo out '.'`	`sb $27,0($26) #echo out '.'`