Reply by Dave Helsley ●November 21, 20012001-11-21
I bet you could do

UART_RBR_A_REG + (8*selectedUart) = somevalue I need to write

I do this kind of branch elimination optimization all the time.

Good luck,
Dave Helsley

----- Original Message -----
From: <>
To: <>
Sent: Monday, November 19, 2001 11:57 AM
Subject: [c54x] ioport > I have a UART chip with two Uarts on it, and the registers are mapped
> into memory locations 0-7 for Uart A and 8-15 for Uart B.
>
> I have them defined like this:
>
> #define UART_RBR_A_REG port0
> #define UART_THR_A_REG port0
> #define UART_IER_A_REG port1
> #define UART_IIR_A_REG port2
> #define UART_FCR_A_REG port2
> #define UART_LCR_A_REG port3
> #define UART_MCR_A_REG port4
> #define UART_LSR_A_REG port5
> #define UART_MSR_A_REG port6
> #define UART_SCR_A_REG port7
>
> // uart B registers
> #define UART_RBR_B_REG port8
> #define UART_THR_B_REG port8
> #define UART_IER_B_REG port9
> #define UART_IIR_B_REG porta
> #define UART_FCR_B_REG porta
> #define UART_LCR_B_REG portb
> #define UART_MCR_B_REG portc
> #define UART_LSR_B_REG portd
> #define UART_MSR_B_REG porte
> #define UART_SCR_B_REG portf > I also have a enumerated type like this :
> typedef enum
> {
> UART_A = 0x00,
> UART_B = 0x01,
> } UartSelect, *PUartSelect;
>
> with a variable declared as :
> UartSelect selectedUart;
>
> what I would like to be able to do is like this:
>
> UART_RBR_A_REG + selectedUart = somevalue I need to write
>
> Instead of doing this
>
> If(selectedUArt == UART_A)
> {
> UART_RBR_A_REG = somevalue;
> }
> else
> {
> UART_RBR_B_REG = somevalue;
> } > Is there a way of doing this? > Carl Chipman
> Nomadics, Inc.
>
> http://www.nomadics.com > _____________________________________
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Reply by ●November 19, 20012001-11-19
I have a UART chip with two Uarts on it, and the registers are mapped
into memory locations 0-7 for Uart A and 8-15 for Uart B.

I have them defined like this:

#define UART_RBR_A_REG port0
#define UART_THR_A_REG port0
#define UART_IER_A_REG port1
#define UART_IIR_A_REG port2
#define UART_FCR_A_REG port2
#define UART_LCR_A_REG port3
#define UART_MCR_A_REG port4
#define UART_LSR_A_REG port5
#define UART_MSR_A_REG port6
#define UART_SCR_A_REG port7

// uart B registers
#define UART_RBR_B_REG port8
#define UART_THR_B_REG port8
#define UART_IER_B_REG port9
#define UART_IIR_B_REG porta
#define UART_FCR_B_REG porta
#define UART_LCR_B_REG portb
#define UART_MCR_B_REG portc
#define UART_LSR_B_REG portd
#define UART_MSR_B_REG porte
#define UART_SCR_B_REG portf I also have a enumerated type like this :
typedef enum
{
UART_A = 0x00,
UART_B = 0x01,
} UartSelect, *PUartSelect;

with a variable declared as :
UartSelect selectedUart;

what I would like to be able to do is like this:

UART_RBR_A_REG + selectedUart = somevalue I need to write

Instead of doing this

If(selectedUArt == UART_A)
{
UART_RBR_A_REG = somevalue;
}
else
{
UART_RBR_B_REG = somevalue;
} Is there a way of doing this? Carl Chipman
Nomadics, Inc.

http://www.nomadics.com