Coding Example | CS+ V4.01.00

8.3 Coding Example

Examples of boot.asm and cstart.asm are shown below.

boot.asm

    ; if using eiint as table reference method,

    ; enable next line's macro.

    ;USE_TABLE_REFERENCE_METHOD .set 1

;-----------------------------------------------------------------------------

;   exception vector table

;-----------------------------------------------------------------------------

    .section "RESET_PE1", text

    .align   512

    jr32     __start   ; RESET

    .align   16

    jr32     _Dummy    ; SYSERR

    .align   16

    jr32     _Dummy    ; HVTRAP

    .align   16

    jr32     _Dummy    ; FETRAP

    .align   16

    jr32     _Dummy_EI ; TRAP0

    .align   16

    jr32     _Dummy_EI ; TRAP1

    .align   16

    jr32     _Dummy    ; RIE

    .align   16

    jr32     _Dummy_EI ; FPP/FPI

    .align   16

    jr32     _Dummy    ; UCPOP

    .align   16

    jr32     _Dummy    ; MIP/MDP

    .align   16

    jr32     _Dummy    ; PIE

    .align   16

    jr32     _Dummy    ; Debug

    .align   16

    jr32     _Dummy    ; MAE

    .align   16

    jr32     _Dummy    ; (R.F.U)

    .align   16

    jr32     _Dummy    ; FENMI

    .align   16

    jr32     _Dummy    ; FEINT

    .align   16

    jr32     _Dummy_EI ; INTn(priority0)

    .align   16

    jr32     _Dummy_EI ; INTn(priority1)

    .align   16

    jr32     _Dummy_EI ; INTn(priority2)

    .align   16

    jr32     _Dummy_EI ; INTn(priority3)

    .align   16

    jr32     _Dummy_EI ; INTn(priority4)

    .align   16

    jr32     _Dummy_EI ; INTn(priority5)

    .align   16

    jr32     _Dummy_EI ; INTn(priority6)

    .align   16

    jr32     _Dummy_EI ; INTn(priority7)

    .align   16

    jr32     _Dummy_EI ; INTn(priority8)

    .align   16

    jr32     _Dummy_EI ; INTn(priority9)

    .align   16

    jr32     _Dummy_EI ; INTn(priority10)

    .align   16

    jr32     _Dummy_EI ; INTn(priority11)

    .align   16

    jr32     _Dummy_EI ; INTn(priority12)

    .align   16

    jr32     _Dummy_EI ; INTn(priority13)

    .align   16

    jr32     _Dummy_EI ; INTn(priority14)

    .align   16

    jr32     _Dummy_EI ; INTn(priority15)

    .section "EIINTTBL_PE1", const

    .align   512

    .dw      #_Dummy_EI ; INT0

    .dw      #_Dummy_EI ; INT1

    .dw      #_Dummy_EI ; INT2

    .rept    512 - 3

    .dw      #_Dummy_EI ; INTn

    .endm

    .section ".text", text

    .align   2

_Dummy:

    br       _Dummy

_Dummy_EI:

    br       _Dummy_EI

;-----------------------------------------------------------------------------

;   startup

;-----------------------------------------------------------------------------

    .section ".text", text

    .align   2

    .public  __start

__start:

$if 1    ; initialize register

    $nowarning

    mov      r0, r1

    $warning

    mov      r0, r2

    mov      r0, r3

    mov      r0, r4

    mov      r0, r5

    mov      r0, r6

    mov      r0, r7

    mov      r0, r8

    mov      r0, r9

    mov      r0, r10

    mov      r0, r11

    mov      r0, r12

    mov      r0, r13

    mov      r0, r14

    mov      r0, r15

    mov      r0, r16

    mov      r0, r17

    mov      r0, r18

    mov      r0, r19

    mov      r0, r20

    mov      r0, r21

    mov      r0, r22

    mov      r0, r23

    mov      r0, r24

    mov      r0, r25

    mov      r0, r26

    mov      r0, r27

    mov      r0, r28

    mov      r0, r29

    mov      r0, r30

    mov      r0, r31

    ldsr     r0, 0, 0       ;  EIPC

    ldsr     r0, 16, 0      ;  CTPC

$endif

$if 1

    ; jump to entry point of each PE

    stsr     0, r10, 2      ; get HTCFG0

    shr      16, r10        ; get PEID

    cmp      1, r10

    bz       .L.entry_PE1

    cmp      2, r10

    bz       .L.entry_PE2

    cmp      3, r10

    bz       .L.entry_PE3

    cmp      4, r10

    bz       .L.entry_PE4

    cmp      5, r10

    bz       .L.entry_PE5

    cmp      6, r10

    bz       .L.entry_PE6

    cmp      7, r10

    bz       .L.entry_PE7

__exit:

    br       __exit

.L.entry_PE1:

    jarl     _hdwinit_PE1, lp ; initialize hardware

$ifdef USE_TABLE_REFERENCE_METHOD

    mov       #__sEIINTTBL_PE1, r6

    jarl      _set_table_reference_method, lp ; set table reference method

$endif

    jr32      __cstart_pm1

.L.entry_PE2:

    jarl      _hdwinit_PE2, lp ; initialize hardware

;$ifdef USE_TABLE_REFERENCE_METHOD

;   mov       #__sEIINTTBL_PE2, r6

;   jarl      _set_table_reference_method, lp ; set table reference method

;$endif

;   jr32      __cstart_pm2

    br        __exit

.L.entry_PE3:

    br        __exit

.L.entry_PE4:

    br        __exit

.L.entry_PE5:

    br        __exit

.L.entry_PE6:

    br        __exit

.L.entry_PE7:

    br        __exit

$endif

;-----------------------------------------------------------------------------

; hdwinit_PE1

; Specify RAM addresses suitable to your system if needed.

;-----------------------------------------------------------------------------

    GLOBAL_RAM_ADDR     .set    0

    GLOBAL_RAM_END      .set    0

    LOCAL_RAM_PE1_ADDR  .set    0

    LOCAL_RAM_PE1_END   .set    0

    .align    2

_hdwinit_PE1:

    mov       lp, r29           ; save return address

    ; clear Global RAM

    mov       GLOBAL_RAM_ADDR, r6

    mov       GLOBAL_RAM_END, r7

    jarl      _zeroclr4, lp

    ; clear Local RAM PE1

    mov       LOCAL_RAM_PE1_ADDR, r6

    mov       LOCAL_RAM_PE1_END, r7

    jarl      _zeroclr4, lp

    mov       r29, lp

    jmp       [lp]

;-----------------------------------------------------------------------------

; hdwinit_PE2

; Specify RAM addresses suitable to your system if needed.

;-----------------------------------------------------------------------------

    LOCAL_RAM_PE2_ADDR  .set    0

    LOCAL_RAM_PE2_END   .set    0

    .align    2

_hdwinit_PE2:

    mov       lp, r14           ; save return address

    ; clear Local RAM PE2

    mov       LOCAL_RAM_PE2_ADDR, r6

    mov       LOCAL_RAM_PE2_END, r7

    jarl      _zeroclr4, lp

    mov       r14, lp

    jmp       [lp]

;-----------------------------------------------------------------------------

;   zeroclr4

;-----------------------------------------------------------------------------

    .align    2

_zeroclr4:

    br        .L.zeroclr4.2

.L.zeroclr4.1:

    st.w      r0, [r6]

    add       4, r6

.L.zeroclr4.2:

    cmp       r6, r7

    bh        .L.zeroclr4.1

    jmp       [lp]

$ifdef USE_TABLE_REFERENCE_METHOD

;-----------------------------------------------------------------------------

;   set table reference method

;-----------------------------------------------------------------------------

    ; interrupt control register address

    ICBASE    .set 0xfffeea00

    .align    2

_set_table_reference_method:

    ldsr      r6, 4, 1      ; set INTBP

    ; Some interrupt channels use the table reference method.

    mov       ICBASE, r10   ; get interrupt control register address

    set1      6, 0[r10]     ; set INT0 as table reference

    set1      6, 2[r10]     ; set INT1 as table reference

    set1      6, 4[r10]     ; set INT2 as table reference

    jmp       [lp]

$endif

;-------------------- end of start up module -------------------;

cstart.asm

;-----------------------------------------------------------------------------

;   system stack

;-----------------------------------------------------------------------------

STACKSIZE    .set    0x200

    .section ".stack.bss", bss

    .align   4

    .ds      (STACKSIZE)

    .align   4

_stacktop:

;-----------------------------------------------------------------------------

;   section initialize table

;-----------------------------------------------------------------------------

    .section ".INIT_DSEC.const", const

    .align   4

    .dw      #__s.data, #__e.data, #__s.data.R

    .section ".INIT_BSEC.const", const

    .align   4

    .dw      #__s.bss, #__e.bss

;-----------------------------------------------------------------------------

;   startup

;-----------------------------------------------------------------------------

    .section ".text.cmn", text

    .public  __cstart_pm1

    .align   2

__cstart_pm1:

    mov      #_stacktop, sp     ;  set sp register

    mov      #__gp_data, gp     ;  set gp register

    mov      #__ep_data, ep     ;  set ep register

    mov      #__s.INIT_DSEC.const, r6

    mov      #__e.INIT_DSEC.const, r7

    mov      #__s.INIT_BSEC.const, r8

    mov      #__e.INIT_BSEC.const, r9

    jarl32   __INITSCT_RH, lp   ;  initialize RAM area

    ; set various flags to PSW via FEPSW

    stsr     5, r10, 0          ; r10 <- PSW

    movhi    0x0001, r0, r11

    or       r11, r10

    ldsr     r10, 5, 0          ; enable FPU

    movhi    0x0002, r0, r11

    ldsr     r11, 6, 0          ; initialize FPSR

    ldsr     r0, 7, 0           ; initialize FPEPC

    ;xori    0x0020, r10, r10   ; enable interrupt

    ;movhi   0x4000, r0, r11

    ;or      r11, r10           ; supervisor mode -> user mode

    ldsr     r10, 3, 0          ; FEPSW <- r10

    mov      #_exit, lp         ; lp <- #_exit

    mov      #_main, r10

    ldsr     r10, 2, 0          ; FEPC <- #_main

    ; apply PSW and PC to start user mode

    feret

_exit:

    br       _exit              ;  end of program

;-----------------------------------------------------------------------------

;   dummy section

;-----------------------------------------------------------------------------

    .section    ".data", data

.L.dummy.data:

    .section    ".bss", bss

.L.dummy.bss:

    .section    ".const", const

.L.dummy.const:

    .section    ".text", text

.L.dummy.text:

;-------------------- end of start up module -------------------;