Enable PortH as GPIO
Posted: Fri May 14, 2010 3:37 pmAll GPIO signals are mapped to device pins. The Syscon DeviceCfg register contains four bits that control mapping of the GPIO Ports to device pins: GonK, EonIDE, GonIDE, and HonIDE. Default all ports E, G and H are set to IDE mode. To use them as GPIO, you must set '1' to appropriate bits in DeviceCfg register.
The DeviceCfg register
Address: 0x8093_0080 - Read/Write, Software locked
Default: 0x0000_0000
Definition: Device Configuration Register. This register controls the operation of major system functions.
Bit functions for ports: PortE - bit 8, port G - bit 10, port H - bit 11
Functions:
EonIDE: 0 - GPIO Port E used for IDE; 1 - GPIO Port E used for GPIO;
GonIDE: 0 - GPIO Port G used for IDE; 1 - GPIO Port G used for GPIO
HonIDE: 0 - GPIO Port H used for IDE; 1 - GPIO Port H used for GPIO.
The Device config register is part of Syscon register block.
The SW Lock field identifies registers with a software lock. A software lock prevents the register from being written (unless an unlock operation is performed immediately prior to the write). Any register whose accidental alteration could cause system damage may be controlled with a software lock. Each peripheral with software lock capability has its own software lock register. A software lock register must be written with 0xAA before each register write to change the values of the control registers.
For all Syscon registers there is a single software lock register: SysSWLock
Address: 0x8093_00C0 - Read/Write
Default: 0x0000_0000
Definition: Syscon Software Lock Register. Provides software control port for all Syscon locked registers. Writing the LOCK field to 0xAA opens the lock. Reading the register will return 0x0000_0001 when the lock is open, and all zeros when the lock is closed (locked).
Bit Descriptions:
RSVD: Reserved. Unknown During Read.
LOCK: Lock code value. This field must be written to a value of 0xAA to open the software lock. Reads 0x01 when the lock is open, 0x00 when the lock is closed.
The DeviceCfg register
- DeviceCFG.png (16.87 KiB) Viewed 34273 times
Address: 0x8093_0080 - Read/Write, Software locked
Default: 0x0000_0000
Definition: Device Configuration Register. This register controls the operation of major system functions.
Bit functions for ports: PortE - bit 8, port G - bit 10, port H - bit 11
Functions:
EonIDE: 0 - GPIO Port E used for IDE; 1 - GPIO Port E used for GPIO;
GonIDE: 0 - GPIO Port G used for IDE; 1 - GPIO Port G used for GPIO
HonIDE: 0 - GPIO Port H used for IDE; 1 - GPIO Port H used for GPIO.
The Device config register is part of Syscon register block.
- Syscon1.png (101.35 KiB) Viewed 34274 times
The SW Lock field identifies registers with a software lock. A software lock prevents the register from being written (unless an unlock operation is performed immediately prior to the write). Any register whose accidental alteration could cause system damage may be controlled with a software lock. Each peripheral with software lock capability has its own software lock register. A software lock register must be written with 0xAA before each register write to change the values of the control registers.
For all Syscon registers there is a single software lock register: SysSWLock
- SysSWLock.png (8.82 KiB) Viewed 34273 times
Address: 0x8093_00C0 - Read/Write
Default: 0x0000_0000
Definition: Syscon Software Lock Register. Provides software control port for all Syscon locked registers. Writing the LOCK field to 0xAA opens the lock. Reading the register will return 0x0000_0001 when the lock is open, and all zeros when the lock is closed (locked).
Bit Descriptions:
RSVD: Reserved. Unknown During Read.
LOCK: Lock code value. This field must be written to a value of 0xAA to open the software lock. Reads 0x01 when the lock is open, 0x00 when the lock is closed.
