Re: [ECOS] HAL register write problem

[Jonathan Larmour <jlarmour@redhat.com>]

jeremy wrote:
> 
> My platform is Samsung KS32C50100, which operates in big-endian mode.
> I got some problem with writing to register using HAL_WRITE function.
> For example, in plf_stub.c where I put the UART initialization function
> in,
> Here I write some initialize value to UART control registers,
>  HAL_WRITE_UINT8 (CYG_DEVICE_SERIAL_RS232_UART_UTXBUF, 0x0);
>  HAL_WRITE_UINT8 (CYG_DEVICE_SERIAL_RS232_UART_URXBUF, 0x0);
>  HAL_WRITE_UINT16(CYG_DEVICE_SERIAL_RS232_UART_UBRDIV, 0x280);
> 
> The first two lines for writing 8-bits registers works fine. But the
> last line doesn't write
> anything into the 16-bits register. I defined that 16-bits register
> like this in the first part
> of the program:
> #define CYG_DEVICE_SERIAL_RS232_UART_UBRDIV \
>     ((volatile cyg_uint16 *) CYG_DEVICE_SERIAL_RS232_UART_BASE + 0x14)

At a guess, you were probably intending to write

#define CYG_DEVICE_SERIAL_RS232_UART_UBRDIV \
    ((volatile cyg_uint16 *) (CYG_DEVICE_SERIAL_RS232_UART_BASE + 0x14))

because adding 0x14 to something cast to a pointer to a 16-bit type will
increment it by 2*0x14=0x28 bytes.

Jifl
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