The MCUXpresso SDK provides a peripheral driver for the KeyPad Port block of MCUXpresso SDK devices.
KPP: KeyPad Port Driver
KPP Initialization Operation
The KPP Initialize is to initialize for common configure: gate the KPP clock, configure columns, and rows features. The KPP Deinitialize is to ungate the clock.
KPP Basic Operation
The KPP provide the function to enable/disable interrupts. The KPP provide key press scanning function KPP_keyPressScanning. This API should be called by the Interrupt handler in application. KPP still provides functions to get and clear status flags.
Typical use case
uint8_t kpp_config_t::activeRow |
uint8_t kpp_config_t::activeColumn |
uint16_t kpp_config_t::interrupt |
A logical OR of "kpp_interrupt_enable_t".
This enumeration uses one-bot encoding to allow a logical OR of multiple members. Members usually map to interrupt enable bits in one or more peripheral registers.
Enumerator |
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kKPP_keyDepressInterrupt |
Keypad depress interrupt source.
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kKPP_keyReleaseInterrupt |
Keypad release interrupt source.
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Enumerator |
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kKPP_ClearKeyDepressSyncChain |
Keypad depress interrupt status.
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kKPP_SetKeyReleasesSyncChain |
Keypad release interrupt status.
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This function ungates the KPP clock and initializes KPP. This function must be called before calling any other KPP driver functions.
- Parameters
-
base | KPP peripheral base address. |
configure | The KPP configuration structure pointer. |
void KPP_Deinit |
( |
KPP_Type * |
base | ) |
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This function gates the KPP clock. As a result, the KPP module doesn't work after calling this function.
- Parameters
-
base | KPP peripheral base address. |
static void KPP_EnableInterrupts |
( |
KPP_Type * |
base, |
|
|
uint16_t |
mask |
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) |
| |
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inlinestatic |
- Parameters
-
base | KPP peripheral base address. |
mask | KPP interrupts to enable. This is a logical OR of the enumeration :: kpp_interrupt_enable_t. |
static void KPP_DisableInterrupts |
( |
KPP_Type * |
base, |
|
|
uint16_t |
mask |
|
) |
| |
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inlinestatic |
- Parameters
-
base | KPP peripheral base address. |
mask | KPP interrupts to disable. This is a logical OR of the enumeration :: kpp_interrupt_enable_t. |
static uint16_t KPP_GetStatusFlag |
( |
KPP_Type * |
base | ) |
|
|
inlinestatic |
- Parameters
-
base | KPP peripheral base address. |
- Returns
- The status of the KPP. Application can use the enum type in the "kpp_interrupt_enable_t" to get the right status of the related event.
static void KPP_ClearStatusFlag |
( |
KPP_Type * |
base, |
|
|
uint16_t |
mask |
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) |
| |
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inlinestatic |
- Parameters
-
base | KPP peripheral base address. |
mask | KPP mask to be cleared. This is a logical OR of the enumeration :: kpp_interrupt_enable_t. |
static void KPP_SetSynchronizeChain |
( |
KPP_Type * |
base, |
|
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uint16_t |
mask |
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) |
| |
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inlinestatic |
- Parameters
-
base | KPP peripheral base address. |
mask | KPP mask to be cleared. This is a logical OR of the enumeration :: kpp_sync_operation_t. |
void KPP_keyPressScanning |
( |
KPP_Type * |
base, |
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|
uint8_t * |
data, |
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uint32_t |
clockSrc_Hz |
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) |
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This function will scanning all columns and rows. so all scanning data will be stored in the data pointer.
- Parameters
-
base | KPP peripheral base address. |
data | KPP key press scanning data. The data buffer should be prepared with length at least equal to KPP_KEYPAD_COLUMNNUM_MAX * KPP_KEYPAD_ROWNUM_MAX. the data pointer is recommended to be a array like uint8_t data[KPP_KEYPAD_COLUMNNUM_MAX]. for example the data[2] = 4, that means in column 1 row 2 has a key press event. |
clockSrc_Hz | Source clock. |