AN2591

Using the External Memory Interface for I/O expansion

17/19

Example of software that gets the value on the 16-bit buffer inputs and writes it in the 16-bit

latch outputs. The two devices are available in bank0 (CSn.x = CSn.0):

int main(void)

{

u16 a;

u16 *Buffer_Data16_in = (u16*)0x60000002; /* Initialize the buffer

address to 0x60000002 */

u16 *Latch_Data16_out = (u16*)0x60000001; /* Initialize the latch

address to 0x60000001 */

*(u16*)0x6C000000 = 0x8005; /* Configure EMI_BCON0 register:

- 16 bit data bus wide

- 1 wait state

- Enable bank 0 */

while(1)

{

a = *Buffer_Data16_in; /* Get the value available on inputs

of the external buffer */

*Latch_Data16_out = a; /* Write this value in the external

latch */

}

}