Sync the two valid signals to keep a fixed phase relationship between
the Rx ant Tx channels, this way avoiding +/- 1 sample differences
on the Tx-Rx latency between consecutive transfers.
Cleanup placement constraints and let the tool have more freedom to
place and route the design. This is possible only after balancing the
memory and system clocks.
Minimize skew on synchronous CDC timing paths between clocks originating
from the same MMCM source. (sys_mem_clk and sys_cpu_clk)
This is required mostly by the smart interconnect.
The CLOCK_DELAY_GROUP property must be applied directly to the output net of BUFGs.
- Add parameter for input data delay time to easily match the one of the
adc_trigger.
- Change the trigger delay path to match between the internal and
external(adc_trigger delays).
"prepare_incremental_compile" is defined as a phony target, but is also a
prerequisite of a real target. This will lead to a complete project build
every time make is called.
To fix the issue the functionality of prepare_incremental_compile target
was included in the generic project build target.
The ready signal of the SYNC interface should be always 1'b1,
regardless of ASYNC_SPI_VALUE.
Drive the ready with one in both branches of the ASYNC_SPI_CLK
generate block.
Currently trigger out pin is hold for 1ms in the next translation(t+1)
state(0 or 1). But not in the state that follows (t+2). This commit
fixes this issue and simplifies the logic.
The previous channel sync mechanism was simply holding the transmission by
pulling down the dma_rd_en of the two DMAs for each channel(set reg 0x50). After a
period of time (that will take the two DMAs to have the data ready to move)
the dma_rd_en was set for both channels, resulting in a synchronized start.
This mechanism is valid when the two channels are streaming the same
type of data (constant, waveform, buffer or math) at close frequencies.
Streaming 10MHz on a channel and 100KHz on the second one will result
in different interpolation factors being used for the two channels.
The interpolation counter runs only when the dma_transfer_suspended(reg 0x50)
is cleared. Because of this, different delays are added by the interpolation
counter one DMA with continuous dma_rd_en will have data earlier than the
one with dma_rd_en controlled by the interpolation counter. Furthermore,
because the interpolation counter value is not reset at each
dma_transfer_suspended, the phase shift between the 2 channels will
differ at each start of transmission.
To make the transfer start synced immune to the above irregularities a
sync_transfer_start register was added (bit 1 of the 0x50 reg).
When this bit is set and the bit 0(dma_transfer_suspended) is toggled,
the interpolation counters are reset. Each channel enables it's DMA until
valid data is received, then it waits for the adjacent channel to get valid data.
This mechanism will be simplified in a future update by using a streaming
interface between the axi_dac_interpolate and the DMAs that does not require
the probing of the DMA.
The decimation module controls the valid signal. The whole triggering mechanism
is active only when the valid signal is active.
In the case of low sampling rates, the valid signal is active once every
n clock cycles. If an external trigger condition is fulfilled and the data valid
signal is low at the time, that trigger will be ignored by the DMA.
To solve this issue, the trigger is held high until the valid is asserted.
And it stays high for at least one clock cycle.
The trigger signal that goes to the DMA(fifo_wr_sync) does not pass through
the variable fifo, for this reason, a 3 clock cycles delay is required, to
keep in sync the data with the trigger.
On the other hand, to be able to cascade the axi_logic_analyzer with
axi_adc_trigger, there should be small delays on the trigger path, for this
reason the trigger_out_adc was created.
Remove the extra delays on the trigger_i(external trigger pins).
- Add embedded trigger as an option. The use of the embedded trigger as an
option in the data stream is done for further processing, keeping the data
synchronized with the trigger.
When instrument (module) trigger is desired (logic_analyzer - adc_trigger),
a small propagation time is required, hence the need to remove the
util_extract(trigger extract) module from the data path.
- Add more options for the IO triggering. This will open the door for multiple
M2k synchronization(triggering).
trigger_o mux:
1 - trigger flag (from regmap)
2 - external pin trigger (Ti)
3 - external pin trigger (To)
4 - internal adc trigger
5 - logic analyzer trigger
The signal passed to trigger_o must not be delayed, but the new value has to be
kept for a short period, 1ms (100000 clock cycles), to reduce switch noises in
the system.
The axi_adc_trigger handles 3 output triggers:
- trigger_o - external trigger (1 clock cycle delay)
- trigger_out - signals on dmac/fifo_wr_sync the start of a new transfer.
A variable fifo depth is present in the data path, which delays the data
arriving at the DMA with 3 clock cycles. By coincidence, the external trigger
is synchronized and detected on 3 clock cycles. To get a maximum optimization
the trigger_out will be delayed with 3 clock cycles for internal triggers and
directly forwarded in the case of an external trigger.
- trigger_out_la (cascade trigger for logic_analyzer - m2k example)
Because the trigger_out_la must have a small delay, to get a realible
instrument triggering mechanism, a 1 delay clock cycle must be added on the
trigger paths, to avoid creating a closed combinatorial loop.
Increase pcore version. The major version 3 is used to describe the instrument
trigger updates.
Software has to know which TIA channel was used for a particular capture.
Define an additional dummy ADC channel which will provide this
information. Currently this channel is always enabled.
This commit was created by squashing the following commits, these
messages were kept just for sake of history:
ad9694_500ebz: Mirror the SPI interface to FMCB
ad9694_500ebz: Set transceiver reference clock to 250
ad9694_500ebz: Allow to configure number of lanes, number of converters
and sample rate
axi_ad9694: Fix number of lanes, it must be 2
ad9694_500ebz: Update the mirrored spi pin assignments
ad9694_500ebz: Gate SPI MISO signals based on chip-select
ad9694_500ebz: Set channel pack sample width
ad9694_500ebz: Change reference clock location
ad9694_500ebz: Remove transceiver memory map arbitration
ad9694_500ebz: Ensure ADC FIFO DMA_DATA_WIDTH is not larger ADC_DATA_WIDTH
ad9694_500ebz: Adjust breakout board pin locations
ad_fmclidar1_ebz: Rename the ad9694_500ebz project
ad_fmclidar1_ebz: Fix lane mapping
ad_fmclidar1_ebz: Delete deprecated files
ad_fmclidar1_ebz: Integrate the axi_laser_driver into the design
ad_fmclidar1_ebz: OTW is an active low signal
ad_fmclidar1_ebz: zc706: Fix iic_dac signals assignment
ad_fmclidar1_ebz: Switch to util_adcfifo
ad_fmclidar1_ebz: Enable synced capture for the fifo
ad_fmclidar1_ebz/zc706: Enable CAPTURE_TILL_FULL
ad_fmclidar1_ebz/zc706: Reduce FIFO size to 2kB
ad_fmclidar1_ebz: Laser driver runs on ADC's core clock
ad_fmclidar1_ebz_bd: Delete the FIFO instance
Because the DMA transfers are going to be relatively small (< 2kbyte),
the DMA can handle the data rate, even when the frequency of the laser
driver pulse is set to its maximum value. (200 kHz)
The synchronization will be done by connecting the generated pulse to
the DMA's SYNC input. Although, to support 2 or 1 channel scenarios, we
need to use the util_axis_syncgen module to make sure that the DMA
catches the pulse, in cases when the pulse width is too narrow. (SYNC is
captures when valid and ready is asserted)
Also we have to reset the cpack IP before each pulse, to keep the DMA buffer's
relative starting point in time fixed, when only 2 or 1 channel is
active.
The module can receive a synchronous or asynchronous pulse with an arbitrary
width and generate a SYNC signal for the DMA Source AXI Streaming interface.
This way we can synchronize the DMA transfers to an external
pulse/signal.
Laszlo Nagy
Istvan Csomortani
AndreiGrozav
sarpadi
StancaPop
Stanca Pop
István Csomortáni
Nick Pillitteri