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Return Values

MCU registers are always used for function return values. The following table lists the return types and the registers used for each.

Return Type Registers Storage Format
bit Carry Flag  
char, unsigned char, 1-byte ptr R7  
int, unsigned int, 2-byte ptr R6 & R7 MSB in R6, LSB in R7
long, unsigned long R4-R7 MSB in R4, LSB in R7
float R4-R7 32-Bit IEEE format
generic ptr R1-R3 Memory type in R3, MSB R2, LSB R1
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