Tlc Component's Memory Mapped Registers

Register Summary

Offset	Register Name	R/W	Reset Value (hex)
Tlc's Block of Configuration Registers
0x00	SoftReset	R/W	00000000
0x04	TickPeriod	R/W	0000000F
0x08 - 0x10	LightPeriod [ 3 ]	R/W	005F5E10
0x14 - 0x1C	Reserved [ 3 ]	N/A	N/A
Tlc's Block of Status Registers
0x20	LightState	R	00000000
0x24	CountdownState	R	00000000

Register Descriptions

Bits	Field Name	Description	R/W	Reset Value	Value Type
31	ResetFlag	When set to '1' the Tlc component is held in its soft reset state. Register values can be written while in the soft reset state, but the Tlc's other logic is inactive. Also, when in soft reset, the values of the GreenVal, AmberVal and RedVal bit-fields define the state of the green, amber and red lights respectively, providing a software over-ride mechanism for the lights.	R/W	0	binary
30:3	Reserved	N/A	N/A	N/A	N/A
2	GreenVal	This defines the value of the green light when the Tlc is in soft-reset state (i.e. when the ResetFlag is '1').	R/W	0	unsigned
1	AmberVal	This defines the value of the amber light when the Tlc is in soft-reset state (i.e. when the ResetFlag is '1').	R/W	0	binary
0	RedVal	This defines the value of the red light when the Tlc is in soft-reset state (i.e. when the ResetFlag is '1').	R/W	0	binary

TickPeriod

Offset: 0x04

Controls the period of the Tlc's tick. See the TickHalfPeriod bit-field for more details.

Bits	Field Name	Description	R/W	Reset Value	Value Type
31:4	Reserved	N/A	N/A	N/A	N/A
3:0	TickHalfPeriod[3:0]	Defines half of the desired period in clock cycles for one tick of the Tlc's countdown. The countdown is used by the internal circuitry of the Tlc to determine the term of activation for each light in the cycle. This should be set to half of the desired period, less one. For a desired period of N this bit-field should be set to N/2-1. Values: 15 : POINT6_US_AT_50MHZ For a 50MHz clock this value results in a TickPeriod of 0.6 microseconds.	R/W	15	unsigned

Bits

Field Name

Description

R/W

Reset Value

Value Type

31:4

Reserved

N/A

3:0

TickHalfPeriod[3:0]

Defines half of the desired period in clock cycles for one tick of the Tlc's countdown. The countdown is used by the internal circuitry of the Tlc to determine the term of activation for each light in the cycle. This should be set to half of the desired period, less one. For a desired period of N this bit-field should be set to N/2-1.

Values:

15 : POINT6_US_AT_50MHZ: For a 50MHz clock this value results in a TickPeriod of 0.6 microseconds.

R/W

unsigned

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LightPeriod [ 3 ]

Offset: 0x08 - 0x10

The bit-fields of this register array control the term of activation for green, amber, and red lights. The array index (offset) for green, amber and red are 2, 1, and 0 respectively.

Bits	Field Name	Description	R/W	Reset Value	Value Type
31:0	ActiveTicks[31:0]	The number of ticks (not cycles) for which a given light is active. The number of clock cycles for which a given light will be active is equal to 2(TickHalfPeriod+1)ActiveTicks. This bit-field should not be set to zero for normal operation. Values: 6250000 : FOUR_S_AT_POINT6_US_TICKS When the TickPeriod is configured to 0.6 microseconds, then this setting will result in a 4 second activation period.	R/W	6250000	unsigned

Bits

Field Name

Description

R/W

Reset Value

Value Type

31:0

ActiveTicks[31:0]

The number of ticks (not cycles) for which a given light is active. The number of clock cycles for which a given light will be active is equal to 2*(TickHalfPeriod+1)*ActiveTicks. This bit-field should not be set to zero for normal operation.

Values:

6250000 : FOUR_S_AT_POINT6_US_TICKS: When the TickPeriod is configured to 0.6 microseconds, then this setting will result in a 4 second activation period.

R/W

6250000

unsigned

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LightState

Offset: 0x20

Bit-fields of this register provide information regarding the current state of the Tlc component. This can be used for testing, debugging, and diagnostics.

Bits	Field Name	Description	R/W	Reset Value	Value Type
31:3	Reserved	N/A	N/A	N/A	N/A
2	Green	This bit provides the current state of the green light. A value of '1' indicates that the light is on and '0' indicates that the light is off.	R	0	binary
1	Amber	This bit provides the current state of the amber light. A value of '1' indicates that the light is on and '0' indicates that the light is off.	R	0	binary
0	Red	This bit provides the current state of the red light. A value of '1' indicates that the light is on and '0' indicates that the light is off.	R	0	binary

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CountdownState

Offset: 0x24

Provides information regarding the current countdown state of the Tlc component. This can be used for testing, debugging, and diagnostics. See the Countdown bit-field for more information.

Bits	Field Name	Description	R/W	Reset Value	Value Type
31:0	Countdown[31:0]	The countdown is used by the Tlc's internal circuitry to keep track of how long a given light (i.e. green, amber, red) should be active before transitioning to the next light in the sequence. Upon a light transition (e.g. green to amber), the countdown is loaded with the value of the ActiveTicks register for the light that is becoming active. For each tick, the countdown is decremented and when this reaches zero a light transition occurs.	R	0	unsigned

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