AN3350 datasheet(176/185 Pages) STMICROELECTRONICS

176 / 185 page

eTPU specific features

AN3350

176/185

Doc ID 018512 Rev 2

eTPU specific features

This chapter describes the eTPU specific features in the compiler:

●

Restrictions on 32-bit variables

●

Host interface files

●

eTPU functions structure

●

pragma ETPU_function

●

Memory allocation

●

Channel structure

●

Tooth Program Register (TPR) structure

●

struct tpr_struct <varname> @ tpr;

●

Entry table intrinsic functions

●

Predefined symbols

●

Integer types

●

Fractional types

●

Inline assembly

●

#pragma write

●

#pragma fill

●

__attribute__((expects_flags))

●

__attribute__((no_save_registers))

●

__attribute__((pure_assembly))

●

eTPU intrinsic functions

23.1

Restrictions on 32-bit variables

eTPU has limited support for 32 bit variables. This is due to 24 bit natural word size of

eTPU. You can declare 32 bit variables, and perform moves (assignments). This allows

larger values to be moved around. Math operations are not supported for 32-bit values.

●

Pointers to functions are not supported.

●

Floating point are not supported.

●

Standard libraries are not provided.

23.2

Host interface files

The compiler creates files intended for the CPU program, which configures eTPU. These

files are named as:

filename_CPU.letter

Where filename is the base name of the eTPU source file being compiled, and letter is an

alphabet letter from a to z.

AN3350 Datasheet(PDF) 176 Page - STMicroelectronics

AN3350 Datasheet(HTML) 176 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