Datasheet

102 PSoC Designer IDE Guide, Document # 001-42655 Rev *B

Assembler

Functions with more complex input parameters or return values can be written using these tables.

Note that the #pragma fastcall16 has replaced #pragma fastcall and use of #pragma fastcall is dep-

recated.

Table 5-6. Pragma Fastcall16 Conventions for Argument Passing

Argument Type Register Argument Register

Single Byte A The argument is passed in A.

Two Single Bytes A, X The first argument is passed in A, the second in X.

Double Byte X, A The MSB is passed in X, the LSB in A.

Pointer A, X The MSB is passed in A, the LSB in X.

All Others None

Arguments are stored on the stack in standard byte order and in

reverse order or appearance. In other words, the MSB of the last

actual parameter is pushed first and the LSB of the first actual

parameter is pushed last.

Table 5-7. Pragma Fastcall16 Conventions for Return Value

Return Type

Return

Comment

Single Byte A The argument is returned in A.

Double Byte X, A The MSB is passed in X, the LSB in A.

Pointer A, X The MSB is passed in A, the LSB in X.

All Others None

Use a pass-by-reference parameter or global variable instead of

returning arguments longer than 16 bits.