LCD - Liquid Crystal Display#
Liquid Crystal Display (LCD) Peripheral API.
This module contains functions to control the LDC peripheral of Silicon Labs 32-bit MCUs and SoCs. The LCD driver can drive up to 8x36 segmented LCD directly. The animation feature makes it possible to have active animations without the CPU intervention.
Modules#
Enumerations#
MUX setting.
Wave type.
Bias setting.
Contrast Configuration.
Frame Counter Clock Prescaler, FC-CLK = FrameRate (Hz) / this factor.
Update Data Control.
Auto Load address which will start the synchronization from CLK_BUS to CLK_PER.
Animation Shift operation; none, left or right.
Animation Logic Control, how AReg and BReg should be combined.
Animation Location, set the LCD segments which animation applies to.
Charge redistribution control.
DMA mode of operation.
Functions#
Initialize the Liquid Crystal Display (LCD) controller.
Configure Update Control.
Initialize the LCD Frame Counter.
Configure the LCD controller Animation feature.
Enables a given LCD segment line.
Enables a given LCD COM line.
Set a given DMA mode operation.
Turn on or clear a segment.
Update 0-31 lowest segments on a given COM-line in one operation according to the bit mask.
Configure the contrast level on the LCD panel.
Configure the bias level on the LCD panel.
Configure the bias level for a specific segment line for Direct Segment Control.
Configure the bias level for a specific segment line.
Configure the mode for the LCD panel.
Configure the charge redistribution cycles for the LCD panel.
Wait for load synchronization completion.
Wait for the LCD to complete resetting or disabling procedure.
Enable or disable LCD controller.
Reset the LCD.
Enable or disable LCD Animation feature.
Enable or disable the LCD blink.
Disable all segments while keeping segment state.
Enable or disable LCD Frame counter.
Enable or disable the LCD Display counter.
Return the current animation state.
Return the current blink state.
Start the synchronization process.
Stop the synchronization process.
Get pending LCD interrupt flags.
Get enabled and pending LCD interrupt flags.
Set one or more pending LCD interrupts from SW.
Enable LCD interrupts.
Disable LCD interrupts.
Clear one or more interrupt flags.
Enable or disable LCD Direct Segment Control.
Macros#
Default Clock Prescaler.
Default LCD Frame Rate Divisor.
Default LCD Contrast.
Maximum common lines of LCD.
Maximum segment lines of LCD.
Default configuration for LCD initialization structure, enables 160 segments.
Frame counter uses a maximum of 5 bits (FCTOP[5:0]).
Enumeration Documentation#
LCD_Mux_TypeDef#
LCD_Mux_TypeDef
MUX setting.
Enumerator | |
---|---|
lcdMuxStatic | Static (segments can be multiplexed with LCD_COM[0]). |
lcdMuxDuplex | Duplex / 1/2 Duty cycle (segments can be multiplexed with LCD_COM[0:1]). |
lcdMuxTriplex | Triplex / 1/3 Duty cycle (segments can be multiplexed with LCD_COM[0:2]). |
lcdMuxQuadruplex | Quadruplex / 1/4 Duty cycle (segments can be multiplexed with LCD_COM[0:3]). |
LCD_Wave_TypeDef#
LCD_Wave_TypeDef
Wave type.
Enumerator | |
---|---|
lcdWaveLowPower | Low power optimized waveform output. |
lcdWaveNormal | Regular waveform output. |
LCD_Bias_TypeDef#
LCD_Bias_TypeDef
Bias setting.
Enumerator | |
---|---|
lcdBiasStatic | Static (2 levels). |
lcdBiasOneHalf | 1/2 Bias (3 levels). |
lcdBiasOneThird | 1/3 Bias (4 levels). |
lcdBiasOneFourth | 1/4 Bias (5 levels). |
LCD_Mode_Typedef#
LCD_Mode_Typedef
Contrast Configuration.
Mode of operation.
Enumerator | |
---|---|
lcdModeStepDown | External cap with resistor string. |
lcdModeChargePump | External cap and internal oscillator. |
LCD_FCPreScale_TypeDef#
LCD_FCPreScale_TypeDef
Frame Counter Clock Prescaler, FC-CLK = FrameRate (Hz) / this factor.
Enumerator | |
---|---|
lcdFCPrescDiv1 | Prescale Div 1. |
lcdFCPrescDiv2 | Prescale Div 2. |
lcdFCPrescDiv4 | Prescale Div 4. |
lcdFCPrescDiv8 | Prescale Div 8. |
LCD_UpdateCtrl_TypeDef#
LCD_UpdateCtrl_TypeDef
Update Data Control.
Enumerator | |
---|---|
lcdUpdateCtrlRegular | Regular update, data transfer done immediately. |
lcdUpdateCtrlFCEvent | Data transfer done at Frame Counter event. |
lcdUpdateCtrlFrameStart | Data transfer done at Frame Start. |
lcdUpdateCtrlDisplayEvent | Data transfer done at Display Counter event. |
LCD_LoadAddr_TypeDef#
LCD_LoadAddr_TypeDef
Auto Load address which will start the synchronization from CLK_BUS to CLK_PER.
Enumerator | |
---|---|
lcdLoadAddrNone | Starts synchronizing registers after a write to BACTRL. |
lcdLoadAddrBactrl | Starts synchronizing registers after a write to BACTRL. |
lcdLoadAddrAregA | Starts synchronizing registers after a write to AREGA. |
lcdLoadAddrAregB | Starts synchronizing registers after a write to AREGB. |
lcdLoadAddrSegd0 | Starts synchronizing registers after a write to SEGD0. |
lcdLoadAddrSegd1 | Starts synchronizing registers after a write to SEGD1. |
lcdLoadAddrSegd2 | Starts synchronizing registers after a write to SEGD2. |
lcdLoadAddrSegd3 | Starts synchronizing registers after a write to SEGD3. |
LCD_AnimShift_TypeDef#
LCD_AnimShift_TypeDef
Animation Shift operation; none, left or right.
Enumerator | |
---|---|
lcdAnimShiftNone | No shift. |
lcdAnimShiftLeft | Shift segment bits left. |
lcdAnimShiftRight | Shift segment bits right. |
LCD_AnimLogic_TypeDef#
LCD_AnimLogic_TypeDef
Animation Logic Control, how AReg and BReg should be combined.
Enumerator | |
---|---|
lcdAnimLogicAnd | Use bitwise logic AND to mix animation register A (AREGA) and B (AREGB). |
lcdAnimLogicOr | Use bitwise logic OR to mix animation register A (AREGA) and B (AREGB). |
LCD_AnimLoc_TypeDef#
LCD_AnimLoc_TypeDef
Animation Location, set the LCD segments which animation applies to.
Enumerator | |
---|---|
lcdAnimLocSeg0To7 | Animation appears on segments 0 to 7. |
lcdAnimLocSeg8To15 | Animation appears on segments 8 to 15. |
LCD_ChargeRedistribution_TypeDef#
LCD_ChargeRedistribution_TypeDef
Charge redistribution control.
Enumerator | |
---|---|
lcdChargeRedistributionDisable | Disable charge redistribution. |
lcdChargeRedistributionEnable | Use 1 prescaled low frequency clock cycle for charge redistribution. |
lcdChargeRedistributionTwoCycle | Use 2 prescaled low frequency clock cycle for charge redistribution. |
lcdChargeRedistributionThreeCycle | Use 3 prescaled low frequency clock cycle for charge redistribution. |
lcdChargeRedistributionFourCycle | Use 4 prescaled low frequency clock cycle for charge redistribution. |
LCD_DmaMode_Typedef#
LCD_DmaMode_Typedef
DMA mode of operation.
Enumerator | |
---|---|
lcdDmaModeDisable | No DMA requests are generated. |
lcdDmaModeFrameCounterEvent | DMA request on frame counter event. |
lcdDmaModeDisplayEvent | DMA request on display counter event. |
Function Documentation#
LCD_Init#
void LCD_Init (const LCD_Init_TypeDef * lcdInit)
Initialize the Liquid Crystal Display (LCD) controller.
Type | Direction | Argument Name | Description |
---|---|---|---|
const LCD_Init_TypeDef * | [in] | lcdInit | A pointer to the initialization structure which configures the LCD controller. |
Configures the LCD controller. You must enable it afterwards, potentially configuring Frame Control and interrupts first according to requirements.
LCD_UpdateCtrl#
void LCD_UpdateCtrl (LCD_UpdateCtrl_TypeDef ud)
Configure Update Control.
Type | Direction | Argument Name | Description |
---|---|---|---|
LCD_UpdateCtrl_TypeDef | [in] | ud | Configures the LCD update method. |
LCD_FrameCountInit#
void LCD_FrameCountInit (const LCD_FrameCountInit_TypeDef * fcInit)
Initialize the LCD Frame Counter.
Type | Direction | Argument Name | Description |
---|---|---|---|
const LCD_FrameCountInit_TypeDef * | [in] | fcInit | A pointer to the Frame Counter initialization structure. |
LCD_AnimInit#
void LCD_AnimInit (const LCD_AnimInit_TypeDef * animInit)
Configure the LCD controller Animation feature.
Type | Direction | Argument Name | Description |
---|---|---|---|
const LCD_AnimInit_TypeDef * | [in] | animInit | A pointer to the LCD Animation initialization structure. |
LCD_SegmentEnable#
void LCD_SegmentEnable (uint32_t seg_nbr, bool enable)
Enables a given LCD segment line.
Type | Direction | Argument Name | Description |
---|---|---|---|
uint32_t | [in] | seg_nbr | Segment line number. |
bool | [in] | enable | Boolean true to enable a segment, false to disable. |
LCD_ComEnable#
void LCD_ComEnable (uint8_t com, bool enable)
Enables a given LCD COM line.
Type | Direction | Argument Name | Description |
---|---|---|---|
uint8_t | [in] | com | COM line number. |
bool | [in] | enable | Boolean true to enable a COM , false to disable. |
LCD_DmaModeSet#
void LCD_DmaModeSet (LCD_DmaMode_Typedef mode)
Set a given DMA mode operation.
Type | Direction | Argument Name | Description |
---|---|---|---|
LCD_DmaMode_Typedef | [in] | mode | DMA mode. |
LCD_SegmentSet#
void LCD_SegmentSet (int com, int bit, bool enable)
Turn on or clear a segment.
Type | Direction | Argument Name | Description |
---|---|---|---|
int | [in] | com | A COM line to change. |
int | [in] | bit | A bit index indicating which field to change. |
bool | [in] | enable | True will set segment, false will clear segment. |
Note
For the Gecko Family, the maximum configuration is (COM-lines x Segment-Lines) 4x40. For the Tiny Gecko Family, the maximum configuration is 8x20 or 4x24. For the Giant Gecko Family, the maximum configuration is 8x36 or 4x40. For the Series 2 Family, the maximum configuration is 4x20. For the Series 2 xG28, the maximum configuration is 8x24 or 4x28.
LCD_SegmentSetLow#
void LCD_SegmentSetLow (int com, uint32_t mask, uint32_t bits)
Update 0-31 lowest segments on a given COM-line in one operation according to the bit mask.
Type | Direction | Argument Name | Description |
---|---|---|---|
int | [in] | com | Indicates a COM line to update. |
uint32_t | [in] | mask | A bit mask for segments 0-31. |
uint32_t | [in] | bits | A bit pattern for segments 0-31. |
LCD_ContrastSet#
void LCD_ContrastSet (int level)
Configure the contrast level on the LCD panel.
Type | Direction | Argument Name | Description |
---|---|---|---|
int | [in] | level | The contrast level in range 0-63. |
LCD_BiasSet#
void LCD_BiasSet (LCD_Bias_TypeDef bias)
Configure the bias level on the LCD panel.
Type | Direction | Argument Name | Description |
---|---|---|---|
LCD_Bias_TypeDef | [in] | bias | The bias level. |
LCD_BiasSegmentSet#
void LCD_BiasSegmentSet (int segmentLine, int biasLevel)
Configure the bias level for a specific segment line for Direct Segment Control.
Type | Direction | Argument Name | Description |
---|---|---|---|
int | [in] | segmentLine | A segment line number. |
int | [in] | biasLevel | The bias configuration level. This value must be within the constraints defined by the LCD_DISPCTRL bias settings. For more information, see the applicable Reference Manual and data sheet. |
Note
When DSC is active, each configuration takes up 4 bits in the corresponding Segment Registers (SEGD0L/SEGD1H for Series 0 and 1, SEGDx/SEGDxH for Series 2) which defines the bias level. For optimal use of this feature, the entire SEGD-registers should be set at once in an optimized routine. Therefore, this function shows how to correctly configure the bias levels and should be used with care.
LCD_BiasComSet#
void LCD_BiasComSet (int comLine, int biasLevel)
Configure the bias level for a specific segment line.
Type | Direction | Argument Name | Description |
---|---|---|---|
int | [in] | comLine | A COM line number, between 0 and 7 for Series 0 and 1. For Series 2, max is LCD_COM_NUM, defined in device-specific headers. |
int | [in] | biasLevel | The bias configuration level. This value must be within the constraints defined by the LCD_DISPCTRL bias settings. For more information, see the appropriate Reference Manual and data sheet. |
Note
When DSC is active, each configuration takes up 4 bits in the corresponding Segment Registers (SEGD4L/SEGD4H for Series 0 and 1, AREGA/AREGB for Series 2) which defines bias level. For optimal use of this feature, the entire register set should be set at once in a optimized routine. Therefore, this function shows how to correctly configure the bias levels and should be used with care.
LCD_ModeSet#
void LCD_ModeSet (LCD_Mode_Typedef mode)
Configure the mode for the LCD panel.
Type | Direction | Argument Name | Description |
---|---|---|---|
LCD_Mode_Typedef | [in] | mode | A mode. |
LCD_ChargeRedistributionCyclesSet#
void LCD_ChargeRedistributionCyclesSet (uint8_t cycles)
Configure the charge redistribution cycles for the LCD panel.
Type | Direction | Argument Name | Description |
---|---|---|---|
uint8_t | [in] | cycles | Charge redistribution cycles, range 0-4. |
LCD_LoadBusyWait#
void LCD_LoadBusyWait (void )
Wait for load synchronization completion.
Type | Direction | Argument Name | Description |
---|---|---|---|
void | N/A |
Note
Doing any writes to HV registers will not go through and will cause a bus fault.
LCD_ReadyWait#
void LCD_ReadyWait (void )
Wait for the LCD to complete resetting or disabling procedure.
Type | Direction | Argument Name | Description |
---|---|---|---|
void | N/A |
LCD_Enable#
void LCD_Enable (bool enable)
Enable or disable LCD controller.
Type | Direction | Argument Name | Description |
---|---|---|---|
bool | [in] | enable | If true, enables LCD controller with current configuration. If false, disables LCD controller. Enable CMU clock for LCD for correct operation. |
LCD_Reset#
void LCD_Reset (void )
Reset the LCD.
Type | Direction | Argument Name | Description |
---|---|---|---|
void | N/A |
LCD_AnimEnable#
void LCD_AnimEnable (bool enable)
Enable or disable LCD Animation feature.
Type | Direction | Argument Name | Description |
---|---|---|---|
bool | [in] | enable | Boolean true enables animation, false disables animation. |
LCD_BlinkEnable#
void LCD_BlinkEnable (bool enable)
Enable or disable the LCD blink.
Type | Direction | Argument Name | Description |
---|---|---|---|
bool | [in] | enable | Boolean true enables blink, false disables blink. |
LCD_BlankEnable#
void LCD_BlankEnable (bool enable)
Disable all segments while keeping segment state.
Type | Direction | Argument Name | Description |
---|---|---|---|
bool | [in] | enable | Boolean true clears all segments, boolean false restores all segment lines. |
LCD_FrameCountEnable#
void LCD_FrameCountEnable (bool enable)
Enable or disable LCD Frame counter.
Type | Direction | Argument Name | Description |
---|---|---|---|
bool | [in] | enable | Boolean true enables frame counter, false disables frame counter. |
LCD_DisplayCountEnable#
void LCD_DisplayCountEnable (bool enable)
Enable or disable the LCD Display counter.
Type | Direction | Argument Name | Description |
---|---|---|---|
bool | [in] | enable | Boolean true enables display counter, false disables display counter. |
LCD_AnimState#
int LCD_AnimState (void )
Return the current animation state.
Type | Direction | Argument Name | Description |
---|---|---|---|
void | N/A |
Returns
Animation state, in range 0-15.
LCD_BlinkState#
int LCD_BlinkState (void )
Return the current blink state.
Type | Direction | Argument Name | Description |
---|---|---|---|
void | N/A |
Returns
Return value is 1 if segments are enabled, 0 if disabled.
LCD_SyncStart#
void LCD_SyncStart (bool autoload, LCD_LoadAddr_TypeDef load_addr)
Start the synchronization process.
Type | Direction | Argument Name | Description |
---|---|---|---|
bool | [in] | autoload | Flag indicating if the synchronization is started manually with CMD.LOAD (false) or if the synchronization is managed automatically by Auto Load (true). |
LCD_LoadAddr_TypeDef | [in] | load_addr | Address which will start the synchronization from CLK_BUS to CLK_PER when Auto Load is selected. This argument has no effect if 'autoload' is false. |
LCD_SyncStop#
void LCD_SyncStop (bool autoload)
Stop the synchronization process.
Type | Direction | Argument Name | Description |
---|---|---|---|
bool | [in] | autoload | Flag indicating if the synchronization is stopped manually with CMD.CLEAR (false) or if the synchronization managed by Auto Load is disabled (true). |
LCD_IntGet#
uint32_t LCD_IntGet (void )
Get pending LCD interrupt flags.
Type | Direction | Argument Name | Description |
---|---|---|---|
void | N/A |
Returns
Pending LCD interrupt sources. Returns a set of interrupt flags OR-ed together for multiple interrupt sources in the LCD module (LCD_IFS_nnn).
LCD_IntGetEnabled#
uint32_t LCD_IntGetEnabled (void )
Get enabled and pending LCD interrupt flags.
Type | Direction | Argument Name | Description |
---|---|---|---|
void | N/A |
Useful for handling more interrupt sources in the same interrupt handler.
Note
Event bits are not cleared by the use of this function.
Returns
Pending and enabled LCD interrupt sources. Return value is the bitwise AND combination of
the OR combination of enabled interrupt sources in LCD_IEN_nnn register (LCD_IEN_nnn) and
the bitwise OR combination of valid interrupt flags of LCD module (LCD_IF_nnn).
LCD_IntSet#
void LCD_IntSet (uint32_t flags)
Set one or more pending LCD interrupts from SW.
Type | Direction | Argument Name | Description |
---|---|---|---|
uint32_t | [in] | flags | LCD interrupt sources to set to pending. Use a set of interrupt flags OR-ed together to set multiple interrupt sources for the LCD module (LCD_IFS_nnn). |
LCD_IntEnable#
void LCD_IntEnable (uint32_t flags)
Enable LCD interrupts.
Type | Direction | Argument Name | Description |
---|---|---|---|
uint32_t | [in] | flags | LCD interrupt sources to enable. Use a set of interrupt flags OR-ed together to set multiple interrupt sources for LCD module (LCD_IFS_nnn). |
LCD_IntDisable#
void LCD_IntDisable (uint32_t flags)
Disable LCD interrupts.
Type | Direction | Argument Name | Description |
---|---|---|---|
uint32_t | [in] | flags | LCD interrupt sources to disable. Use a set of interrupt flags OR-ed together to disable multiple interrupt sources for LCD module (LCD_IFS_nnn). |
LCD_IntClear#
void LCD_IntClear (uint32_t flags)
Clear one or more interrupt flags.
Type | Direction | Argument Name | Description |
---|---|---|---|
uint32_t | [in] | flags | LCD interrupt sources to clear. Use a set of interrupt flags OR-ed together to clear multiple interrupt sources for LCD module (LCD_IFS_nnn). |
LCD_DSCEnable#
void LCD_DSCEnable (bool enable)
Enable or disable LCD Direct Segment Control.
Type | Direction | Argument Name | Description |
---|---|---|---|
bool | [in] | enable | If true, enables LCD controller Direct Segment Control Segment and COM line bias levels need to be set explicitly with LCD_BiasSegmentSet() and LCD_BiasComSet() function calls respectively. |