MSI MS-98M9, Руководство пользователя

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A-3
GPIO WDT Programming MS-98M9
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 0x12 Bit 0 N_GPO0 0x21 Bit 0
N_GPI1 0x12 Bit 1 N_GPO1 0x21 Bit 1
N_GPI2 0x12 Bit 2 N_GPO2 0x21 Bit 2
N_GPI3 0x42 Bit 3 N_GPO3 0x21 Bit 3
N_GPI4 0x12 Bit 4 N_GPO4 0x21 Bit 4
N_GPI5 0x12 Bit 5 N_GPO5 0x21 Bit 5
N_GPI6 0x12 Bit 6 N_GPO6 0x21 Bit 6
N_GPI7 0x12 Bit 7 N_GPO7 0x21 Bit 7
Note:
GPIO should be accessed through controller device
0x9C
on SMBus. The associated access
method in examples ( SMBus_ReadByte , SMBus_WriteByte ) are provided in part 3.
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 =SMBus_ReadByte (0x9C, 0x21 ); // Read value from
N_GPO0
port through SMBus.
val = val | (1<< 0 ); // Set N_GPO0 address (bit 0) to 1 (output “high”).
SMBus_WriteByte (0x9C, 0x21 , val); // Write back to N_GPO0 port through SMBus.
Example: Set N_GPO1 output “low”
val = SMBus_ReadByte (0x9C, 0x21 ); // Read value from N_GPO1 port through SMBus..
val = val & (~(1<< 1 )); // Set N_GPO1 address (bit 1) to 0 (output “low”).
SMBus_WriteByte (0x9C, 0x21 , val); // Write back to N_GPO1 port through SMBus.
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 = SMBus_ReadByte (0x9C, 0x12 ); // Read value from N_GPI2 port through SMBus.
val = val & (1<< 2 ); // Read N_GPI2 address (bit 2).