PICSimLab troubleshooting guides: firmware loading, simulation, serial ports, MPLAB X and GDB connections, and platform install problems — symptoms, causes and step-by-step fixes.
GDB Cannot Connect to PICSimLab on localhost:1234? Backend Fixes You started your GDB, typed target remote localhost:1234, and got a refusal — or worse, a silent hang. In PICSimLab, remote GDB debugging only exists for some backends, only after you switch it on inside the simulator, and only with the matching GDB flavour for your…
PICSimLab Linux Install Problems: .deb Dependencies, Flatpak and AppImage PICSimLab v0.9.3 gives Linux users three routes — a .deb package, a Flatpak, and an AppImage — and each fails in its own characteristic way: dependency errors from the .deb, a double-click that does nothing from the AppImage, or an installed program that cannot reach serial…
PICSimLab Won’t Open on macOS? Gatekeeper and Wrong-Build Fixes You downloaded the new native macOS build of PICSimLab v0.9.3, dragged it into Applications — and macOS will not open it: a warning dialog, a refusal, or nothing at all. Almost every case is one of two things: Gatekeeper doing its standard job on an internet-downloaded…
ESP32 Firmware Won’t Flash or Boot in PICSimLab? The QIO/QOUT Limit Your ESP32 project flashes — or appears to — and then the simulated board will not boot: it loops, stalls, or shows nothing, even though the same firmware runs on a real DevKitC. With PICSimLab’s QEMU-based ESP32 boards there is one documented limitation behind…
MPLAB X Plugin Cannot Connect to PICSimLab? Port 1234 Checks You installed PICSimLab, opened your project in MPLAB X, started a debug session — and MPLAB X cannot connect to the simulator. The PICSimLab plugin talks to MPLAB X over a plain TCP socket, which makes this failure pleasantly mechanical: it is almost always the…
PICSimLab Serial Port Not Working? Virtual Pair and 8N1 Fixes Your simulated UART is silent: the terminal window shows nothing, or shows garbage, or the port will not open at all. In PICSimLab this is rarely a firmware bug. The desktop simulator’s serial port does not connect to a real COM port by itself —…
PICSimLab Simulation Not Running? Clock, Reset and Workspace Fixes The firmware loads, you press run — and the board just sits there. No blinking, no output, no reaction to buttons. A dead-looking simulation in PICSimLab is usually one of four things: the simulation is not actually running, the board is held in reset or mis-clocked,…
PICSimLab .hex File Not Loading? Board, MCU and File Checks You built your firmware, opened PICSimLab, loaded the .hex file — and nothing happened. Either the load itself fails, or the file appears to load but the board behaves as if no program is there. This page works through the causes in the order they…
