示波器

示波器模块提供用于波形采集、触发和测量的 Python 接口。

概述

用 scope 模块控制示波器，采集模拟信号、在特定事件上触发，并进行自动测量。

导入

from lager import Net, NetType

用法

from lager import Net, NetType

# Get scope net
scope = Net.get('ANALOG1', type=NetType.Analog)

# Enable the channel
scope.enable()

# Start capture
scope.start_capture()

# Take measurements
freq = scope.measurement.frequency()
period = scope.measurement.period()

# Stop and disable
scope.stop_capture()
scope.disable()

方法

通道控制

`enable()`

启用该示波器通道。

scope.enable()

`disable()`

停用该示波器通道。

scope.disable()

采集控制

`start_capture()`

开始连续波形采集。

scope.start_capture()

`start_single_capture()`

开始单次采集（采集一次触发事件）。

scope.start_single_capture()

`stop_capture()`

停止波形采集。

scope.stop_capture()

测量

通过 measurement 属性访问完整的测量功能：

电压测量

# Basic voltage
vmax = scope.measurement.voltage_max()      # Maximum voltage
vmin = scope.measurement.voltage_min()      # Minimum voltage
vpp = scope.measurement.voltage_peak_to_peak()  # Peak-to-peak
vavg = scope.measurement.voltage_average()  # Average voltage
vrms = scope.measurement.voltage_rms()      # RMS voltage

# Waveform characteristics
vtop = scope.measurement.voltage_flat_top()    # Flat top voltage
vbase = scope.measurement.voltage_flat_base()  # Flat base voltage
vamp = scope.measurement.voltage_flat_amplitude()  # Amplitude

# Thresholds
vupper = scope.measurement.voltage_threshold_upper()
vlower = scope.measurement.voltage_threshold_lower()
vmid = scope.measurement.voltage_threshold_mid()

# Signal quality
overshoot = scope.measurement.voltage_overshoot()
preshoot = scope.measurement.voltage_preshoot()

时序测量

# Frequency and period
freq = scope.measurement.frequency()
period = scope.measurement.period()

# Rise and fall times
rise = scope.measurement.rise_time()
fall = scope.measurement.fall_time()

# Pulse widths
pos_width = scope.measurement.pulse_width_positive()
neg_width = scope.measurement.pulse_width_negative()

# Duty cycles
pos_duty = scope.measurement.duty_cycle_positive()
neg_duty = scope.measurement.duty_cycle_negative()

# Time at voltage extremes
t_vmax = scope.measurement.time_at_voltage_max()
t_vmin = scope.measurement.time_at_voltage_min()

# Slew rates
pos_slew = scope.measurement.positive_slew_rate()
neg_slew = scope.measurement.negative_slew_rate()

计数测量

# Edge counts
pos_edges = scope.measurement.positive_edge_count()
neg_edges = scope.measurement.negative_edge_count()

# Pulse counts
pos_pulses = scope.measurement.positive_pulse_count()
neg_pulses = scope.measurement.negative_pulse_count()

面积测量

area = scope.measurement.waveform_area()
period_area = scope.measurement.waveform_period_area()

统计测量

variance = scope.measurement.variance()
pvrms = scope.measurement.voltage_rms_period()  # Period RMS voltage

延迟与相位测量

# Delay measurements (between channels)
rr_delay = scope.measurement.delay_rising_rising_edge()
rf_delay = scope.measurement.delay_rising_falling_edge()
fr_delay = scope.measurement.delay_falling_rising_edge()
ff_delay = scope.measurement.delay_falling_falling_edge()

# Phase measurements
rr_phase = scope.measurement.phase_rising_rising_edge()
rf_phase = scope.measurement.phase_rising_falling_edge()
fr_phase = scope.measurement.phase_falling_rising_edge()
ff_phase = scope.measurement.phase_falling_falling_edge()

测量选项

大多数测量都接受可选参数：

# Keep measurement displayed on scope
freq = scope.measurement.frequency(display=True)

# Enable cursor measurement mode
vpp = scope.measurement.voltage_peak_to_peak(measurement_cursor=True)

串流（PicoScope）

PicoScope 设备支持串流功能：

`stream_start(channel, volts_per_div, time_per_div, trigger_level, trigger_slope, capture_mode, coupling)`

启动串流采集。 参数：

channel（str）：要启用的通道 —— "A"、"B"、"1"、"2"
volts_per_div（float）：垂直刻度
time_per_div（float）：水平刻度，单位秒
trigger_level（float）：触发电平，单位伏特
trigger_slope（str）："rising"、"falling"、"either"
capture_mode（str）："auto"、"normal"、"single"
coupling（str）："dc"、"ac"

scope.stream_start(
    channel="A",
    volts_per_div=1.0,
    time_per_div=0.001,
    trigger_level=0.5,
    trigger_slope="rising",
    capture_mode="auto",
    coupling="dc"
)

`stream_stop()`

停止串流采集。

scope.stream_stop()

`stream_capture(output, duration, samples)`

把数据采集到文件。 参数：

output（str）：输出文件路径
duration（float）：采集时长，单位秒
samples（int）：采样点数（可选）

scope.stream_capture(
    output="waveform.csv",
    duration=5.0
)

完整示例

from lager import Net, NetType
import time

def measure_pwm_signal():
    """Measure PWM signal characteristics."""

    # Get scope net
    pwm_net = Net.get('PWM_OUTPUT', type=NetType.Analog)

    try:
        # Enable channel
        pwm_net.enable()

        # Configure trigger
        pwm_net.trigger_settings.set_mode_normal()
        pwm_net.trigger_settings.set_coupling_DC()
        pwm_net.trigger_settings.edge.set_source(pwm_net)
        pwm_net.trigger_settings.edge.set_slope_rising()
        pwm_net.trigger_settings.edge.set_level(1.65)  # 50% of 3.3V

        # Start capture
        pwm_net.start_capture()
        time.sleep(0.5)  # Wait for stable capture

        # Take measurements
        frequency = pwm_net.measurement.frequency()
        period = pwm_net.measurement.period()

        print(f"PWM Frequency: {frequency:.2f} Hz")
        print(f"PWM Period: {period*1000:.3f} ms")

        # Calculate duty cycle from pulse width if available
        # ...

    finally:
        pwm_net.stop_capture()
        pwm_net.disable()

if __name__ == "__main__":
    measure_pwm_signal()

波形显示设置

通过 trace_settings 配置垂直和水平刻度：

# Vertical scale (V/div)
scope.trace_settings.set_volts_per_div(1.0)
volts = scope.trace_settings.get_volts_per_div()

# Vertical offset
scope.trace_settings.set_volt_offset(0.5)
offset = scope.trace_settings.get_volt_offset()

# Horizontal scale (s/div)
scope.trace_settings.set_time_per_div(0.001)  # 1ms/div
time_scale = scope.trace_settings.get_time_per_div()

# Horizontal offset
scope.trace_settings.set_time_offset(0.0)
time_offset = scope.trace_settings.get_time_offset()

高级触发设置

通过 trigger_settings 访问高级触发配置：

# Trigger mode
scope.trigger_settings.set_mode_auto()
scope.trigger_settings.set_mode_normal()
scope.trigger_settings.set_mode_single()
mode = scope.trigger_settings.get_mode()

# Trigger coupling
scope.trigger_settings.set_coupling_DC()
scope.trigger_settings.set_coupling_AC()
scope.trigger_settings.set_coupling_low_freq_reject()
scope.trigger_settings.set_coupling_high_freq_reject()
coupling = scope.trigger_settings.get_coupling()

# Edge trigger settings
scope.trigger_settings.edge.set_source(scope)
scope.trigger_settings.edge.set_slope_rising()
scope.trigger_settings.edge.set_slope_falling()
scope.trigger_settings.edge.set_slope_both()
scope.trigger_settings.edge.set_level(1.65)

# Get status
status = scope.trigger_settings.get_status()

光标控制

通过 cursor 属性访问光标功能：

# Set cursor positions
scope.cursor.set_a(x=100, y=50)
scope.cursor.set_b(x=200, y=50)

# Get cursor positions
ax, ay = scope.cursor.get_a()
bx, by = scope.cursor.get_b()

# Move cursors relatively
scope.cursor.move_a(x_del=10, y_del=5)
scope.cursor.move_b(x_del=-10, y_del=0)

# Read cursor measurements
x_delta = scope.cursor.x_delta()  # Time difference
y_delta = scope.cursor.y_delta()  # Voltage difference
inv_x = scope.cursor.frequency()  # Frequency

# Get individual values
ax_val = scope.cursor.a_x()
ay_val = scope.cursor.a_y()
bx_val = scope.cursor.b_x()
by_val = scope.cursor.b_y()

# Hide cursor
scope.cursor.hide()

受支持的硬件

厂商	型号系列	特性
Rigol	MSO5000	多通道、混合信号、协议解码
PicoScope	多种型号	支持串流

说明

示波器通道（1-4）请用 NetType.Analog
MSO 示波器的数字通道（D0-D15）请用 NetType.Logic
串流功能仅在 PicoScope 设备上可用
为获得可靠的测量结果，请在开始采集之前先配置触发
测量方法成功时返回 float，测量无效时返回 None（例如无信号、无触发、通道不对）。在 Rigol 硬件上，仪器对无效测量返回 9.9E+37，它会被自动转换为 None
关于协议触发（UART、I2C、SPI、CAN），请参阅逻辑分析仪文档

入门

开发

电源与仿真

测量

I/O 与通信

实用工具

概述

导入

用法

方法

通道控制

`enable()`

`disable()`

采集控制

`start_capture()`

`start_single_capture()`

`stop_capture()`

测量

电压测量

时序测量

计数测量

面积测量

统计测量

延迟与相位测量

测量选项

串流（PicoScope）

`stream_start(channel, volts_per_div, time_per_div, trigger_level, trigger_slope, capture_mode, coupling)`

`stream_stop()`

`stream_capture(output, duration, samples)`

完整示例

波形显示设置

高级触发设置

光标控制

受支持的硬件

说明

​概述

​导入

​用法

​方法

​通道控制

​enable()

​disable()

​采集控制

​start_capture()

​start_single_capture()

​stop_capture()

​测量

​电压测量

​时序测量

​计数测量

​面积测量

​统计测量

​延迟与相位测量

​测量选项

​串流（PicoScope）

​stream_start(channel, volts_per_div, time_per_div, trigger_level, trigger_slope, capture_mode, coupling)

​stream_stop()

​stream_capture(output, duration, samples)

​完整示例

​波形显示设置

​高级触发设置

​光标控制

​受支持的硬件

​说明

概述

导入

用法

方法

通道控制

`enable()`

`disable()`

采集控制

`start_capture()`

`start_single_capture()`

`stop_capture()`

测量

电压测量

时序测量

计数测量

面积测量

统计测量

延迟与相位测量

测量选项

串流（PicoScope）

`stream_start(channel, volts_per_div, time_per_div, trigger_level, trigger_slope, capture_mode, coupling)`

`stream_stop()`

`stream_capture(output, duration, samples)`

完整示例

波形显示设置

高级触发设置

光标控制

受支持的硬件

说明