[SOLVED] Found these Macros in PIC32 Bootloader Code, please explain?

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This is a header file i found, when i am reading the PIC32 Bootloader Code:-

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Code C - [expand]
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#ifndef __UART_H__
#define __UART_H__
 
#define DEFAULT_BAUDRATE            115200
 
#define Ux(y)         U2##y
 
#define UxBRG           Ux(BRG)
#define UxMODE          Ux(MODE)
#define UxSTA           Ux(STA)
#define UxSTAbits       Ux(STAbits)
#define UxSTACLR        Ux(STACLR)
#define UxSTASET        Ux(STASET)
#define UxTXREG         Ux(TXREG)
#define UxRXREG         Ux(RXREG)
 
#define TRANS_LAYER_Init UartInit
#define TRANS_LAYER_Task UartTask
#define TRANS_LAYER_Close UartClose
 
extern void TRANS_LAYER_Init(UINT);
extern void TRANS_LAYER_Task(void);
extern void UartClose(void);
#endif

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I am not able to get what this macro do:-
#define Ux U2##y

What i assume is that the line
#define UxBRG Ux(BRG)
and UxBRG is equilavent to U2BRG

What is this ##?

 

[ponnus]

hai,
Your assumption is correct.

Here, UxBRG is equivalent to U2BRG.

## is the token pasting or token concatenation operator. When the macro is expanded, the tokens on the sides of the operator combines together to form a single token

Regards

 

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Thank You So Much.

What an Operator it is, thanks for telling me one new thing.