/** \brief Check connection between chips
*
* \return true if the connection between chips is OK
*/
bool ksz8051_nandtree_check(void)
{
/* reset the controller and switch to nand tree mode */
io_output_low(MII_PIN_RST);
io_output_low(MII_PIN_INTRP);
// short delay
io_high(MII_PIN_RST);
// delay
/* prepare all pins to NAND tree test */
for (uint32_t i = 0; i < N; i++) {
io_output_high(nand_pins[i]);
}
io_input(MII_PIN_CRS);
// delay
/* process the NAND tree test on CRS (PA0) */
uint32_t nandtree = io_is_set(MII_PIN_CRS) ? 1 : 0;
for (uint32_t i = 0; i < N; i++, nandtree <<= 1) {
io_low(nand_pins[i]);
nandtree |= io_is_set(MII_PIN_CRS) ? 1 : 0;
// short delay
}
/* reset the controller and switch back to the normal mode */
io_low(MII_PIN_RST);
io_high(MII_PIN_INTRP);
io_af(MII_PIN_CRS, MII_AF);
for (uint32_t i = 0; i < N; i++) {
io_af(nand_pins[i], MII_AF);
}
// delay
io_high(MII_PIN_RST);
return (nandtree == 0b10101010101010101);
}
int main(){
io_out(LED);
i2c_init();
while(1){
io_high(LED);
_delay_ms(1000);
io_low(LED);
_delay_ms(1000);
}
}