MSI MS-98L9, Руководство пользователя

Страница: 57 / 58

A-3
GPIO WDT Programming MS-98L9
General Purposed IO
1. General Purposed IO – GPIO/DIO
The GPIO port configuration addresses are listed in the following table:
Name IO Port IO address Name IO Port IO address
N_GPI0 0xA02 Bit 7 N_GPO0 0xA02 Bit 3
N_GPI1 0xA02 Bit 6 N_GPO1 0xA02 Bit 2
N_GPI2 0xA02 Bit 5 N_GPO2 0xA02 Bit 1
N_GPI3
0xA02 Bit 4
N_GPO3
0xA02 Bit 0
1.1 Set output value of GPO
1. Read the value from GPO port.
2. Set the value of GPO address.
3. Write the value back to GPO port.
Example: Set N_GPO0 output “high”
val = Inportb ( 0xA02 ); // Read value from N_GPO0 port.
val = val | (1<< 3 ); // Set N_GPO0 address (bit 3) to 1 (output “high”).
Outportb ( 0xA02 , val); // Write back to
N_GPO0
port.
Example: Set N_GPO1 output “low”
val = Inportb ( 0xA02 ); // Read value from N_GPO1 port.
val = val & (~(1<< 2 )); // Set N_GPO1 address (bit 2) to 0 (output “low”).
Outportb ( 0xA02 , val); // Write back to N_GPO1 port.
1.2 Read input value from GPI
1. Read the value from GPI port.
2. Get the value of GPI address.
Example: Get N_GPI2 input value.
val = Inportb ( 0xA02 ); // Read value from N_GPI2 port.
val = val & (1<< 5 ); // Read N_GPI2 address (bit 5).
if (val) printf (“Input of N_GPI2 is High”);
else printf (“Input of
N_GPI2
is Low”);