4 SUMP Logic Analyzer mode
sys64738 edited this page 2021-08-17 22:21:11 +00:00

Mode 4 provides a SUMP/OLS-compatible logic analyzer interface, usable with sigrok/PulseView etc.

Pinout

Raspberry Pico

On the Raspberry Pico, 16 channels are available:

Pin number Usage Usage Pin number
GP0 stdio UART TX VBUS
GP1 stdio UART RX VSYS
GND <ground> <ground> GND
GP2 3V3 EN
GP3 3V3 OUT
GP4 ADC VREF
GP5 GP28 / ADC2
GND <ground> <ground> GND / AGND
GP6 Channel 0 GP27 / ADC1
GP7 Channel 1 GP26 / ADC0
GP8 Channel 2 RUN
GP9 Channel 3 Test PWM signal GP22
GND <ground> <ground> GND
GP10 Channel 4 Channel 15 GP21
GP11 Channel 5 Channel 14 GP20
GP12 Channel 6 Channel 13 GP19
GP13 Channel 7 Channel 12 GP18
GND <ground> <ground> GND
GP14 Channel 8 Channel 11 GP17
GP15 Channel 9 Channel 10 GP16
<end> <bottom> <bottom> <end>

The implementation has been lifted from picoprobe-sump, for which we thank the author a lot.

Usage

sigrok-cli

sigrok-cli --driver=ols:conn=/dev/ttyACM0 --config samplerate=50Mhz --samples 256 --channels 0-1

PulseView

Select the "Openbench Logic Sniffer" as probe type, select serial connection, where the device should show up. Any baudrate should work.

Alternatively,

pulseview --driver=ols:conn=/dev/ttyACM0

Runtime configuration: overclocking

On some MCUs, the system can temporarily overclock itself to provide a higher sampling rate. This is controlled using the dpctl sump-overclock command, the details are hardware-specific.