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Function Return Values

Function return values are always passed using MCU registers. The following table lists the possible return values and the registers used for each.

Return Type Register Description
bit R4.0 Single bit returned in R4.0.
unsigned char
RL4 Single byte type returned in RL4.
unsigned int,
near pointer
R4 Two byte (16-bit) type returned in R4.
unsigned long,
far pointer,
huge pointer
R4 & R5 LSB in R4, MSB in R5.
float R4 & R5 32-Bit IEEE format.
double R4-R7 64-Bit IEEE format.
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