Nixel 512
The Nixel 512 chip is a recording peripheral that can implement the Synapse Electrical Broadband node. It supports the following ElectricalBroadbandConfig parameters:
| Parameter name | Parameter options |
|---|---|
bit_width | 12 |
sample_rate | 4000, 8000, 16000, 20000, 25000, 32000 |
low_cutoff_hz | 4, 57, 92, 154, 457 (defaults 92 if field is empty) |
high_cutoff_hz | 4365, 13489, 20400 (defaults 13489 if field is empty) |
channels | valid electrode_id and reference_id depend on the desired reference mode |
Gain and Filter Parameters
The Nixel 512 chip has tunable filter parameters and gain settings. The value of the low- and high-frequency cutoffs determines the gain of the system. The table below details the valid pairs of filter cutoff values, as well the gain associated with each setting.
| Low Cutoff (Hz) | High Cutoff (Hz) | Gain (V/V) |
|---|---|---|
| 457 | 13489 | 138 |
| 154 | 13489 | 179 |
| 92 | 13489 | 200 |
| 57 | 13489 | 200 |
| 57 | 4365 | 200 |
| 4 | 20400 | 13 |
Differential Mode
You need to select pairs of electrodes according to the following rules:
electrode_id: Select of set of even numbered electrodes which fall between 0–511, inclusive.reference_id: For a givenelectrode_idn,reference_id= n+1
Global Reference Mode
electrode_id: All even OR all odd values between 0–511, inclusive.reference_id: Refer to the following table:
electrode_id | Valid reference_id |
|---|---|
0–7 | 512 |
8–127 | 513 |
128–135 | 514 |
136–255 | 515 |
256–263 | 516 |
264–383 | 517 |
384–391 | 518 |
392–511 | 519 |
Ground Reference Mode
To use PCB ground as your reference signal:
electrode_id: All even OR all odd values between 0–511, inclusive.reference_id: 520
SciFi Virtual Recording Peripheral
This recording peripheral generates test data for benchmarking and debugging SciFi. It can implement the Electrical Broadband node. The peripheral will attempt to match the bit-rate requested by the supplied config parameters. It supports the following ElectricalBroadbandConfig parameters:
| Parameter name | Parameter options |
|---|---|
bit_width | 12 |
sample_rate | 0–10000 |
gain | Ignored |
low_cutoff_hz | Ignored |
high_cutoff_hz | Ignored |
channels | electrode_id and reference_id are ignored. Test data will output the id of each configured channel at the requested sample rate |