AXI Laser Driver

The AXI Laser Driver IP core generates all the necessary control signals for the ad_fmclidar1_ebz prototyping platform, to drive the laser, switch between the TIA channels and synchronize all the data flow inside the FPGA. This documentation covers the main functionality of the IP core and its software programmable registers.

Features

PWM generator with a free running counter
Software configurable frequency and pulse width for the PWM
Control and status lines for the ADP3624 MOSFET driver
Software configurable interrupts
Software configurable TIA channel sequencer

Files

Name	Description
library/axi_laser_driver/axi_laser_driver.v	Verilog source for the peripheral.

Configuration Parameters

Name	Description	Default Value	Choices/Range
`ID`	Core ID should be unique for each instance of the IP	`0`
`ASYNC_CLK_EN`	Bit must be set if the core clock is different from the AXI Memory Mapped interface clock	`True`
`PULSE_WIDTH`	The pulse width of the generated signal. The resolution is the core clock’s time period.	`7`	From 0 to 2147483647.
`PULSE_PERIOD`	The period of the generated signal. The resolution is the core clock’s time period.	`10`	From 0 to 2147483647.

Interface

s_axi

Standard AXI Slave Memory Map interface

Physical Port	Logical Port	Direction
`s_axi_awaddr`	`AWADDR`	in [15:0]
`s_axi_awprot`	`AWPROT`	in [2:0]
`s_axi_awvalid`	`AWVALID`	in
`s_axi_awready`	`AWREADY`	out
`s_axi_wdata`	`WDATA`	in [31:0]
`s_axi_wstrb`	`WSTRB`	in [3:0]
`s_axi_wvalid`	`WVALID`	in
`s_axi_wready`	`WREADY`	out
`s_axi_bresp`	`BRESP`	out [1:0]
`s_axi_bvalid`	`BVALID`	out
`s_axi_bready`	`BREADY`	in
`s_axi_araddr`	`ARADDR`	in [15:0]
`s_axi_arprot`	`ARPROT`	in [2:0]
`s_axi_arvalid`	`ARVALID`	in
`s_axi_arready`	`ARREADY`	out
`s_axi_rdata`	`RDATA`	out [31:0]
`s_axi_rresp`	`RRESP`	out [1:0]
`s_axi_rvalid`	`RVALID`	out
`s_axi_rready`	`RREADY`	in

s_axi_aclk

Physical Port	Logical Port	Direction	Dependency
`s_axi_aclk`	`CLK`	in

s_axi_aresetn

Physical Port	Logical Port	Direction	Dependency
`s_axi_aresetn`	`RST`	in

ext_clk

An external clock input. If ASYNC_CLK_EN is set, this clock will be used as the core clock.

Physical Port	Logical Port	Direction	Dependency
`ext_clk`	`CLK`	in	`ASYNC_CLK_EN = 1`

Ports

Physical Port	Direction	Description
`driver_en_n`	out	This line will control the MOSFET driver’s shot down pin. If set the MOSFET driver is not working.
`driver_pulse`	out	Generated pulse, which is used to drive the laser
`driver_otw_n`	in	Over temperature warning flag of the MOSFET driver.
`driver_dp_reset`	out	A reset signal, which asserts right before the generated pulse. This signal can be used for preconditioning various IPs of the data path.
`tia_chsel`	out [7:0]	Control lines for the TIA channel multiplexer.
`irq`	out	Interrupt signal.

Register Map

AXI Laser Driver (axi_laser_driver) register map

DWORD	BYTE	Reg Name				Description
		BITS	Field Name	Type	Default Value	Description
`0x0`	`0x0`	`VERSION`				Version of the peripheral. Follows semantic versioning. Current version 1.00.61.
		`[31:16]`	`VERSION_MAJOR`	`RO`	`0x0001`
		`[15:8]`	`VERSION_MINOR`	`RO`	`0x01`
		`[7:0]`	`VERSION_PATCH`	`RO`	`0x61`
`0x1`	`0x4`	`ID`
		`[31:0]`	`ID`	`RO`	`ID`	Value of the ID configuration parameter. In case of multiple instances, each instance will have a unique ID.
`0x2`	`0x8`	`SCRATCH`
		`[31:0]`	`SCRATCH`	`RW`	`0x00000000`	Scratch register useful for debug.
`0x4`	`0x10`	`CONFIG_PWM`				Configuration Registers
		`[0]`	`RESET`	`RW`	`0x1`	Reset bit of the core. By default the core is in reset.
`0x5`	`0x14`	`CONFIG_PERIOD`				Configuration Registers
		`[31:0]`	`PWM_PERIOD`	`RW`	`PULSE_PERIOD`	The period of the generated signal. The resolution is the core clock’s time period. LOAD_CONFIG bit must be asserted to load the registers value into the PWM logic.
`0x6`	`0x18`	`CONFIG_WIDTH`				Configuration Registers
		`[31:0]`	`PWM_WIDTH`	`RW`	`PULSE_WIDTH`	The pulse width of the generated signal. The resolution is the core clock’s time period. LOAD_CONFIG bit must be asserted to load the registers value into the PWM logic.
`0x21`	`0x84`	`STATUS_LDRIVER`				Configuration Registers
		`[0]`	`DRIVER_OTW`	`RO`	`0x0`	The status of the OTW (over temperature warning flag) pin of the MOSFET driver.
`0x22`	`0x88`	`EXT_CLK_MONITOR`				Status Registers
		`[31:0]`	`EXT_CLK_FREQ`	`RO`	`0x00000000`	The core clock’s frequency. This clock is used for example by PWM counter too. The number is represented as unsigned 16.16 format. Assuming a 100MHz processor clock the minimum is 1.523kHz and maximum is 6.554THz.
`0x29`	`0xa4`	`IRQ_PENDING`				Interrupt Registers
		`[0]`	`IRQ_PULSE_PENDING`	`RW1C`	`0x0`	This bit is set if a pulse was generated, and the IRQ_PULSE_MASK bit is not set. Set this bit after the interrupt was handled as required.
		`[1]`	`IRQ_OTW_ENTER_PENDING`	`RW1C`	`0x0`	This bit is set if the MOSFET driver enters in OTW state, and the IRQ_OTW_ENTER_MASK bit is not set. Set this bit after the interrupt was handled as required.
		`[2]`	`IRQ_OTW_EXIT_PENDING`	`RW1C`	`0x0`	This bit is set if the MOSFET driver enters in OTW state, and the IRQ_OTW_EXIT_MASK bit is not set. Set this bit after the interrupt was handled as required.
`0x2a`	`0xa8`	`IRQ_SOURCE`				Interrupt Registers
		`[0]`	`IRQ_PULSE_SOURCE`	`RO`	`0x0`	This bit is set if a pulse was generated. Cleared together with the corresponding IRQ_PENDING bit.
		`[1]`	`IRQ_OTW_ENTER_SOURCE`	`RO`	`0x0`	This bit is set if the MOSFET driver enters in OTW state. Cleared together with the corresponding IRQ_PENDING bit.
		`[2]`	`IRQ_OTW_EXIT_SOURCE`	`RO`	`0x0`	This bit is set if the MOSFET driver exits in OTW state. Cleared together with the corresponding IRQ_PENDING bit.
`0x2b`	`0xac`	`SEQUENCER_CONTROL`				TIA Sequencer Registers
		`[0]`	`SEQUENCER_ENABLE`	`RW`	`0x0`	Set this bit to enable the TIA channel sequencer.
		`[1]`	`AUTO_SEQUENCE_EN`	`RW`	`0x1`	If set, the sequencer runs in auto mode, using the predefined sequence. Otherwise the software must set the TIA_MANUAL_CONFIG register to change the TIA channel selection.
`0x2c`	`0xb0`	`SEQUENCER_OFFSET`				TIA Sequencer Registers
		`[31:0]`	`TIA_CHSEL_OFFSET`	`RW`	`0x00000000`	Defines the time between setting the TIA channel select lines and the next generated pulse.
`0x2d`	`0xb4`	`SEQUENCE_AUTO_CONFIG`				TIA Sequencer Registers
		`[1:0]`	`SEQUENCE_VALUE0`	`RW`	`0x0`	The value of the TIA channel selects lines in the first sequence.
		`[5:4]`	`SEQUENCE_VALUE1`	`RW`	`0x1`	The value of the TIA channel selects lines in the second sequence.
		`[9:8]`	`SEQUENCE_VALUE2`	`RW`	`0x2`	The value of the TIA channel selects lines in the third sequence.
		`[13:12]`	`SEQUENCE_VALUE3`	`RW`	`0x3`	The value of the TIA channel selects lines in the fourth sequence.
`0x2e`	`0xb8`	`TIA_MANUAL_CONFIG`				TIA Sequencer Registers
		`[1:0]`	`TIA0_CHSEL_MANUAL`	`RW`	`0x0`	The value of the TIA0 channel selects lines in manual mode.
		`[5:4]`	`TIA1_CHSEL_MANUAL`	`RW`	`0x0`	The value of the TIA0 channel selects lines in manual mode.
		`[9:8]`	`TIA2_CHSEL_MANUAL`	`RW`	`0x0`	The value of the TIA0 channel selects lines in manual mode.
		`[13:12]`	`TIA3_CHSEL_MANUAL`	`RW`	`0x0`	The value of the TIA0 channel selects lines in manual mode

Access Type	Name	Description
RO	Read-only	Reads will return the current register value. Writes have no effect.
RW	Read-write	Reads will return the current register value. Writes will change the current register value.
RW1C	Read,write-1-to-clear	Reads will return the current register value. Writing the register will clear those bits of the register which were set to 1 in the value written. Bits are set by hardware.

References

HDL IP core at library/axi_laser_driver
AXI Laser Driver on wiki