IFDEF not working, or is it me?
WoF
Posts: 10
Hello, assembler gurus,
what I wanted to achieve is a default clock frequency of 50MHz, being defined in the common include file.
But I wanted the possibility to override the setting in individual source files.
I want to put a statement like MHZ EQU 20, or MHZ EQU 4 in a source file.
In the include I put:
The assembler will not assemble if I don't have MHZ defined in the source.
But this is the·reason why I used the IFDEF statement. In case I didn't define MHZ I want FREQ 50_000_000 to be executed.
In case I defined MHZ, I want FREQ to be set according to the value of MHZ.
This would be fine.
But the assembler complains about the missing symbol MHZ in the IF MHZ = 20 line.
Why? The assembler is not supposed to assemble the lines between IFDEF MHZ and ELSE?
Bug? Or silly me?
what I wanted to achieve is a default clock frequency of 50MHz, being defined in the common include file.
But I wanted the possibility to override the setting in individual source files.
I want to put a statement like MHZ EQU 20, or MHZ EQU 4 in a source file.
In the include I put:
IFDEF MHZ
IF MHZ = 20
FREQ 20_000_000
ENDIF
ELSE
FREQ 50_000_000
ENDIF
The assembler will not assemble if I don't have MHZ defined in the source.
But this is the·reason why I used the IFDEF statement. In case I didn't define MHZ I want FREQ 50_000_000 to be executed.
In case I defined MHZ, I want FREQ to be set according to the value of MHZ.
This would be fine.
But the assembler complains about the missing symbol MHZ in the IF MHZ = 20 line.
Why? The assembler is not supposed to assemble the lines between IFDEF MHZ and ELSE?
Bug? Or silly me?
Comments
Please post the entire program.
Besides that, it is not wise to redefine FREQ.
Instead, demand·that device and freq are set in the application file·
rather than an include file. Then also let define a symbol that represents
the freq so you can have several code sections based on frequency
in your include files. That way you control everything from the application
file.
regards peter
I dropped the idea by now.
But still the strange behaviour of the Assembler persists.
Here is a complete sample. Put it in a.src file and try:
mySym is not defined. The assembler should assemble inc $09, no?
Instead it complains about the line IF mySym<10 in the ELSE clause, which should not be assembled at all, when mySym is not defined.
Also, mySym must be defined BEFORE the IFDEF statement. (That's ok, as long if you know it). But it is NOT alright, that any expression in a conditionally excluded part of the code is evaluated somehow and cause an error which stops the assembly.
This one is ok. No error. If storage is not defined, ds 2 is assembled. The else clause is not evaluated and there is no complaining about storage not being defined.
This one is not ok:
The IF storage = 0 statement will be evaluated somehow and cause the assembly to fail.
But this works
org $100 ;mysym equ 4 ifndef mySym mysym = -1 endif if mysym < 0 inc $09 else if mySym < 10 rept mySym inc $08 endr endif if mySym = 10 call Anything endif endifThe if .. else .. endif works for sure. I use that frequently.
regards peter
Nevertheless, somebody who is responsible for SASM should read that and take in account that there is a leeettle bug in the assembler.
Thanks, Peter, for caring for my problem.
but we couldn't make it work. I used the above trick but with
a compiler variable. And I think that works.
Load the attached program and view list.
It should generate:
1 ;autocreate indirect jumptable 2 0FF8 0BFF device sx18,oschs1 3 =01312D00 freq 20_000_000 4 07FF 0B02 reset reset_entry 5 =00000000 irc_cal irc_slow 6 7 ;------------------------------------ 8 farcall macro 9 curorg = $ 10 ifndef __??\1 11 __??\1 = jmpentry 12 endif 13 if jmpentry >= $FE 14 error "Too many jumpentries" 15 endif 16 if jmpentry = __??\1 17 org __??\1 18 __??\1 19 jmp @\1 20 jmpentry = $ 21 endif 22 org curorg 23 call @__??\1 24 endm 25 ;------------------------------------ 26 27 =00000000 org $000 28 0000 0010 jmp @interrupt 0001 0B00 29 =00000002 jmpentry = $ 30 ;here we want entries 31 ;__farname 32 ; jmp @farname 33 34 =00000100 org $100 35 =00000100 interrupt 36 0100 0C27 mov w,#39 37 0101 000F retiw 38 =00000102 reset_entry 39 =00000102 main 40 farcall target ;this should setup entry __target and call __target 41 =00000102 m curorg = $ 42 m ifndef __target 43 m __target = jmpentry 44 m endif 45 m if jmpentry >= $FE 46 m error "Too many jumpentries" 47 m endif 48 m if jmpentry = __target 49 =00000002 m org __target 50 =00000002 m __target 51 0002 0010 m jmp @target 0003 0B0D 52 =00000004 m jmpentry = $ 53 m endif 54 =00000102 m org curorg 55 0102 0010 m call @__target 0103 0902 57 farcall target2 ;this should setup entry __target2 and call __target2 58 =00000104 m curorg = $ 59 m ifndef __target2 60 m __target2 = jmpentry 61 m endif 62 m if jmpentry >= $FE 63 m error "Too many jumpentries" 64 m endif 65 m if jmpentry = __target2 66 =00000004 m org __target2 67 =00000004 m __target2 68 0004 0010 m jmp @target2 0005 0B0E 69 =00000006 m jmpentry = $ 70 m endif 71 =00000104 m org curorg 72 0104 0010 m call @__target2 0105 0904 74 farcall target ;this should just call __target 75 =00000106 m curorg = $ 76 m ifndef __target 77 m __target = jmpentry 78 m endif 79 m if jmpentry >= $FE 80 m error "Too many jumpentries" 81 m endif 82 m if jmpentry = __target 83 m org __target 84 m __target 85 m jmp @target 86 m jmpentry = $ 87 m endif 88 =00000106 m org curorg 89 0106 0010 m call @__target 0107 0902 91 farcall target2 ;this should just call __target2 92 =00000108 m curorg = $ 93 m ifndef __target2 94 m __target2 = jmpentry 95 m endif 96 m if jmpentry >= $FE 97 m error "Too many jumpentries" 98 m endif 99 m if jmpentry = __target2 100 m org __target2 101 m __target2 102 m jmp @target2 103 m jmpentry = $ 104 m endif 105 =00000108 m org curorg 106 0108 0010 m call @__target2 0109 0904 108 farcall target ;this should just call __target 109 =0000010A m curorg = $ 110 m ifndef __target 111 m __target = jmpentry 112 m endif 113 m if jmpentry >= $FE 114 m error "Too many jumpentries" 115 m endif 116 m if jmpentry = __target 117 m org __target 118 m __target 119 m jmp @target 120 m jmpentry = $ 121 m endif 122 =0000010A m org curorg 123 010A 0010 m call @__target 010B 0902 125 010C 0B02 jmp main 126 127 =0000010D target 128 010D 000D retp 129 130 =0000010E target2 131 010E 000D retp@pjv,
This is what you were after, right?
I have set aside a fixed area for the jumptable so it does require two compilations
if you want to trim that area so no codespace is wasted. The first compilation
will give you the address to be used instead of org $100 (= jmpentry value).
regards peter