AN3350 datasheet(66/185 Pages) STMICROELECTRONICS

66 / 185 page

Working with the assembler

AN3350

66/185

Doc ID 018512 Rev 2

jmp Start+5

; Warning - an expression

jmp There

; OK (assuming a label)

jmp Here

; Warning (a symbol that is not a label)

jmp .

; Warning (a symbol that is not a label)

10.4.6

Code checking

During code analysis, as when the -lint option is used, you can assume that:

●

Every instruction and label defined in the code is reachable.

●

Instructions without a label at their address are reached only after following the

previous instruction. This, in turn, is assumed to originate from the previous address.

●

For every instruction, its following instruction must also be known (this does not include

indirect and scheduler related change of flow instructions).

Deviations from the last convention are flagged as ill-formed code and may cause the tool to

reject input, as shown in Example 5.

Example 5 Deviations from convention in code

Start:

nop

move r1,r12

; can only be executed after the nop

Loop_prefix:

.align 4

; Invalid - current instruction is not known

Loop:

addi r4,1

.word 0x187983

; Invalid - code flow interrupted by data

sub.f r2,r2,r3

jmp.n zero,Loop

nop

; Invalid - what next?

10.5

eTPU assembler preprocessor

The etpu_bins preprocessor enables macro definitions, conditional assembling, and multi-

level file inclusion. These are achieved through preprocessor directives and operations.

Preprocessor directives features lines with special syntax that are recognized and

processed (by the preprocessor) based on their meaning. All directives are placed at the

beginning of the line and start with the pound character (#). With 'operations', the directives

are placed inside lines and are replaced accordingly by the preprocessor.

All objects handled by the preprocessors are sequences of characters called 'tokens'.

Tokens types can be numbers, symbols, attributes, strings and operators. Consequently, the

arguments for some preprocessor directives and operations might be limited to specific

types (e.g. the '#include' directive expects its argument to be a single string) or behave

according to the type of the argument (e.g. the '%str(X)' operation tests for a single string

token).

AN3350 Datasheet(PDF) 66 Page - STMicroelectronics

AN3350 Datasheet(HTML) 66 Page - STMicroelectronics

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 ...More

Datasheet Download

Link URL