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Gwyscope DSP is a shorthand for three boards combo:
- Red Pitaya STEMlab 125-14 (PCB Red Pitaya)
- Mainboard (PCB CMIPITAYA)
- HRDAC board (PCB CMIDAC11001)
Although we designed the boards to be connected in a stack to enhance capabilities of the Red Pitaya (RP), other use cases are possible. For example only RP board and Mainboard might be used to enhance RP with many channels high bit-depth converters or the 20-bit DAC board can be solely controlled by Arduino.
Red Pitaya board
The Red Pitaya board can be bought e.g. from Digikey, search for the IZD0007 product number. This is the older version with Zync 7010 chip. An upgraded board (IZD0029) exists employing more advanced Zync 7020, however we have only (successfully) tried to compile a bitstream for it without any further testing. Nevertheless, our plan is to move to this board in the future.
The standard jumper setting that we use in our labs is the low voltage configuration (±1 V), nevertheless RP can be configured for a high voltage range (±20 V).
Mainboard
The mainboard (PCB CMIPITAYA) is used to provide power supply for RP, it has two 18-bit 8ch ADCs, 16-bit 16ch DAC, input and output voltage buffers, two multiplexers, one CS decoder and one IO expander. It has Eurocard format (160 mm x 100 mm). Since DPS V5 there are jumpers available that allow for bypassing the input and output buffer, so the original RP bandwidth can be restored. The power is supplied by either two Molex connectors (since PCB V6) and/or a 96 pin EURO connector (DIN 41612), see the image below. This right-angle or this straight connectors can be used as counterparts.
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The most important signals on this connector are the ADC_MUX1-16 which go to the 18-bit ADCs and also via multiplexers and buffers to RP's fast inputs. Further, AUX_DAC_OUT1-16 signals connect with the 16-bit DAC, SCAN_DAC_* signals are just feed-through pins when the 20-bit DAC board is connected and RP1_FAST_DAC signals are RP's fast outputs.