Digilent OpenScope MZ Bedienungsanleitung

OpenScope MZ is an open source, multi-function, electronic instrumentation device that can be controlled using a computer or mobile device to acquire, analyze,

visualize, and generate signals from circuits, sensors, and other electronic devices. OpenScope MZ makes it easy to generate analog and digital signals using the power

supply, function generator and GPIO () and measure and visualize analog and digital signals using the oscilloscope and logic analyzer. Develop and debug circuits

faster by generating stimuli and visualizing the response using OpenScope MZ.

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OpenScope MZ Reference Manual

Connectivity

WiFi (802.11g)

USB 2.0 (High Speed Required)

Oscilloscope

2 Channels

12-bit resolution per channel

6.25 MS/s () sample rate

Flat bandwidth up to 1 MHz () at ±0.5dB

2 MHz () of bandwidth at -3dB

1 MΩ of input impedance

±20 V input voltage range

Features

Maximum buffer size of 32640 samples per channel

Arbitrary Waveform Generator

Sine, triangle, sawtooth, square and DC outputs

10-bit resolution

1 Hz () to 1 MHz () frequency

3 V pk2pk output with ±1.5 V offset

10 mA output current

25000 sample buffer size

Logic Analyzer and GPIO ()

10 Channels multiplexed between the Logic Analyzer and as general purpose IO

3.3V CMOS logic for both the Logic Analyzer and GPIO ()

7 mA source and 12 mA sink when used as GPIO ()

Logic Analyzer has a sample rate of 10 MS/s ()

Maximum buffer size of 32640 samples per channel for the Logic Analyzer

Power Supply

2 Channels

±4 V output voltage

50 mA per channel

Other features

Two external triggers

USB powered device

4 user LEDs

PIC32MZ2048EFG124 microcontroller

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mz%3Areference-manual)

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OpenScope MZ J1 Header Pinout

Top Row Bottom Row

1 D8 (8) 2 UART_RX/PWM2 (P5)

3 D7 (7) 4 SPI_CS ()/UART_RTS/PWM1 (P4)

5 D6 (6) 6 SPI_CLK/UART_CTS (P3)

7 D5 (5) 8 SDI/SDO/UART_TX (P2)

9 D4 (4) 10 SDI/SDO (P1)

11 D3 (3) 12 INT ()/CLK2 (C2)

13 D2 (2) 14 DO10 (10)

15 D1 (1) 16 DO9 (9)

17 Trigger Input (T1) 18 Trigger Output (T0)

19 GND () (↓) 20 GND () (↓)

21 AWG1 (W1) 22 INT ()/CLK1 (C1)

23 DC Output 1 (V1) 24 DC Output 2 (V2)

25 GND () (↓) 26 GND () (↓)

27 AI2+/OSC2 (2+) 28 GND ()/AI2- (2-)

29 AI1+/OSC1 (1+) 30 GND ()/AI1- (1-)

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mz%3Areference-manual)

OpenScope MZ uses the ADC () on the PIC32MZ to create a 2 channel oscilloscope with 12-bits of resolution per channel. Each channel has a pair of analog inputs

with a PWM output to facilitate the interleaving of the two inputs, one PWM to handle the input offset voltages, and one DMA channel at the second highest priority

to transfer the measured data.

Walk Around the Board

Oscilloscope

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manual)

To ensure that the ADC () performs accurately, a 3 V reference with feedback must be assumed to be accurate with 0.1% resistors and 10% capacitors.

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The oscilloscope has the following features:

2 Channels

12 bits of resolution per channel

6.25 MS/s () per channel

2 MHz () bandwidth at -3 dB

Input impedance of 1 MΩ

Input voltage range of ±20 V with protection up to ±40 V

Maximum Buffer Size of 32640 samples per channel

Reduced from a maximum size of 32766 samples to account for ADC () warm-up and pre-trigger data, various delay timer overrun sources, and a 4

byte reduction to prevent large DMA stalls when the maximum destination block size is used.

The OpenScope MZ has a single channel 10 MS/s () 10-bit function generator. An R2R resistor ladder with 1% resistors is used in place of a DAC (). Due to the

nature of resistor ladders, it is possible to have a missing code for steps larger than 3 mV or encounter propagation delays, most notably when switching between the

values of 0x1FF and 0x200. The channel uses 10 IO pins on the PIC32MZ to generate the output through the resistor ladder and a DMA channel that is shared with