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New PICs and free compilers Microchip VS Code IDE We use microcontrollers from Microchip Technology in many of our projects; for over 15 years, we have used the MPLAB X IDE to develop the firmware. Now Microchip has released an MPLAB Extension for VS Code IDE. We’ll look into that, plus the latest microcontroller peripherals from Microchip. by Tim Blythman A n IDE (integrated development environment) is a program that can be used to develop software. Many years ago, we used separate text editors, compilers and programming apps to do this task, but an IDE brings these together into a single, integrated environment, making development easier (many IDEs also include an in-circuit debugger). There are also IDEs for native software development (eg, writing Windows software on a Windows computer). However, this article will focus on IDEs for microcontroller firmware development. The MPLAB X IDE is a typical example. It allows you to create projects, edit and compile code, upload firmware to a target device and even run a debugging session to inspect the inner workings and memories of a project as it runs. MPLAB X IDE also offers features such as syntax highlighting, autocompletion and error checking. These sorts of tools require the IDE to be aware of the programming language and the structure of your project, but can be incredibly helpful in picking up errors early. MPLAB X is based on the NetBeans IDE, which was originally intended for the Java language. The following description may be easier to understand if you have had some previous experience with software IDEs and working with microcontrollers, and thus will be familiar with the terminology we will use. If you come across terms you’re not familiar with, you may want to look them up on the internet. VS Code Visual Studio Code (VS Code) is an IDE developed by Microsoft that was first released in 2015. VS Code can be used with a variety of languages and has the ability to install so-called extensions to expand its functionality. According to industry surveys, it has been ranked among the top development tools in recent years. We first noted VS Code in the March 2025 issue, when we introduced the Raspberry Pi Pico 2 microcontroller module (siliconchip.au/ Article/17796). This hardware release coincided with the porting of the C SDK (software development kit) for Raspberry Pi microcontrollers to the VS Code platform. In our review of the PICkit BASIC programmer and debugger (September 2025; siliconchip.au/Article/18849), we noted the release of the MPLAB Extension Pack for VS Code. This allows VS Code to be used as an IDE for project development for PIC microcontrollers and other Microchip Technology parts. That article also noted Fig.1: the splash screen for a recent version (6.30) of MPLAB X IDE hints at the rise of the MPLAB Extension for VS Code. Fig.2: VS Code’s Activity Bar allows quick access to features and extensions. VS Code Explorer Search Source Control Run and Debug Extensions MPLAB MPLAB AI Coding Extension 58 Silicon Chip Australia's electronics magazine siliconchip.com.au Fig.3: the MPLAB Extension Pack includes a few different elements (listed at left) to provide the features needed within an IDE. the inclusion of an AI coding assistant. Recent versions of the MPLAB X IDE seem to indicate (Fig.1) that VS Code will be the main IDE in the future. Of course, older versions of MPLAB X and even its MPLAB IDE predecessor are still available from the Microchip archive at siliconchip.au/link/abpn Like MPLAB X IDE, VS Code is available on multiple platforms, including Windows, Linux and macOS. VS Code can be installed on inexpensive Raspberry Pi computers (which are effectively Linux computers with ARM processors), but it does not appear to be officially supported on that platform. In this article, we will investigate the steps needed to install the MPLAB Extensions in the VS Code IDE to allow working with PIC microcontrollers and explore some features of VS Code. Then we’ll report on some other Microchip news, including new parts. Using VS Code We found that VS Code was easy enough to use, although it does several things very differently to MPLAB X, and there are some MPLAB X features that are still lacking. So it could be somewhat of a learning curve to make the change. We started by downloading it from https://code.visualstudio. com and installing it. siliconchip.com.au The Activity Bar at upper left is a good place to start exploring – Fig.2 shows the Activity Bar and the functions of its buttons. You may not see the lower buttons immediately, since they will be added when the MPLAB Extensions are installed. To install the MPLAB Extensions, click on the Extensions button and search for “MPLAB”. Then install the MPLAB Extension Pack, as seen in Fig.3. This includes several other bundled extensions that are needed. Note that VS Code supports both ‘light’ (black text on white background) and ‘dark’ modes; we have used a mix of screenshots to demonstrate this. Like the MPLAB X IDE, compilers are installed separately. We already had some compilers installed to work with MPLAB X IDE; we did not have to do anything for VS Code to detect and use these. If you need to install a compiler, we suggest installing the latest compilers from siliconchip.au/ link/acd7 For example, if you plan to work with 8-bit PIC microcontrollers (PIC12, PIC16, PIC18), you should install the XC8 compiler. For 32-bit parts like the PIC32 chips used in many Micromites, you should install the XC32 compiler. We also found that we did not need to install tool packs (for programmers) and device family packs (DFPs), which Australia's electronics magazine also appear to have been detected after being installed by the MPLAB X IDE. You may see a prompt at the bottom right corner of the VS Code window to install these or other software dependencies. VS Code also has a strong security focus. So you might also see prompts to ‘trust’ a folder. This should be fine for MPLAB projects, but be aware that VS Code can also work with code that can run on the host computer. So be cautious about trusting other projects, especially those that can run natively on your computer. Getting started Click on the MPLAB button on the Activity Bar and open the Welcome page from the Help → Welcome menu, if it is not already showing. That should show a button for Getting Started with MPLAB. Click on that and you should see a screen like Fig.5. This page is a good base from which to navigate until you become more familiar with VS Code. You can open an MPLAB X project if you have previously used MPLAB X to create one. Our firmware downloads for construction projects involving microcontrollers often include the MPLAB X projects and files, so you could download and experiment with one of those. November 2026  59 Fig.4: the Command Palette is a VS Code feature that provides access to search, as well as allowing commands to be entered as text. Fig.5 (below): the MPLAB Welcome Screen provides some useful starting points for PIC projects within VS Code. Fig.6: even at the start of a chat with the MPLAB AI Assistant, it is analysing the project files to provide insights into how to improve the code. MPLAB Extensions for VS Code uses a different project format, so changes made in VS Code are not reflected in the MPLAB X project properties, although changes to the source code are. We generally made copies of our projects so that the changes made by the two IDEs did not conflict. The Explorer (top button of the Activity Bar) should show the various files associated with the project. Most of the project properties are held in JSON files in a “.vscode” subfolder. JSON files are in text format and are generally human readable, so they 60 Silicon Chip can be edited if necessary. The Projects section of the MPLAB activity also shows the hierarchy of the JSON file and clicking on a field will open up a user-friendly view that resembles the Project Properties windows from the MPLAB X IDE. VS Code makes use of ‘Workspaces’, which generally include a project folder in their scope, although other folders can be added. The File menu contains options relating to Workspaces. You can drag-and-drop the buttons from the Activity Bar, as well as other sub-windows, and move items around to customise the work area. There are buttons to toggle the two sidebars and many more layout options under the View menu (Appearance and Editor Layout submenu items). Another interesting tool is the ‘Command Palette’, which looks like a search box at the centre top (by default) of the VS Code window. Fig.4 shows the drop-down that is seen when you click on the Command Palette. You can use the key combinations shown in Fig.4 to enter text into the Command Palette to search for a file, symbol or text or to run a command. It also shows handy defaults and recent Australia's electronics magazine actions. It’s a powerful way to access features when you are constantly using the keyboard while coding. Also see https://aka.ms/vscodekeybindings Using the MPLAB Extensions for VS Code is straightforward enough, and we found most of the problems we ran into were due to unfamiliarity with the layout and environment. We had no trouble compiling, using ‘>build’ in the Command Palette to perform a “MPLAB CMake: Build”. The MPLAB panel (selected from the Activity Bar) should show any connected programmers under the Tools dropdown. You can also use the Run menu to access programming and debugging options. MPLAB AI Coding Assistant To use the AI Assistant, you will require an API key, which in turn requires a free Microchip Technology account; this can be created at https:// login.microchip.com Once you have set up the account and logged in, you can copy the API key from www.microchip.com/ai-­ assistant/accesskey You will also need to have the Microchip Chatbot selected and using the MPLAB Agent. siliconchip.com.au Fig.7: the AI Assistant can also suggest code changes that can be accepted or rejected, as shown here. Note how we have asked it to keep, but comment out, the old code for reference. This view shows dark mode (white text on black). Opening the AI chat window from the Activity Bar should prompt for the API key if it is needed. The interface is much the same as other AI chatbots, where you type in a question or prompt and the AI agent processes the query and responds. Sometimes it will pause and ask for permission to review an online resource. Context is important, so we started our chat (Fig.6) with a brief statement about the relevant facts that related to our project and asked for a review. The analysis stretched for a few pages beyond what is shown here. It included several correct observations and some suggestions of what to work on. Fig.7 shows the end result of two further prompts. The first prompt was a request to modify a function to change the Peripheral Module Disable (PMD) registers so that only the IOC (interrupt on change) peripheral is enabled; this is done to minimise siliconchip.com.au power consumption in sleep mode while allowing sleep to be ended by a pin change interrupt. The AI Assistant made an appropriate suggestion, and the editing window provides the option to reject or accept the change in place. Instead of accepting, we asked it to comment out the old code instead of replacing it; the result is shown in Fig.7 and accepted as looking correct to us. We were similarly able to generate startup code to switch off the PMD registers. The AI Assistant was asked to scan the code for peripheral usage and suggest appropriate values to enable only the peripherals that are used by the code. Its assessment of the necessary peripherals was quite good, although it did take a bit of troubleshooting to get the exact values needed. In this case, the AI Assistant was helpful in suggesting troubleshooting strategies such as disabling each peripheral, one Australia's electronics magazine at a time, to try to identify the problematic case. We found that the AI Assistant was quite helpful in avoiding the tunnel vision that can sometimes occur during troubleshooting and could suggest alternatives to those that had been considered. It’s almost like having someone else to share the problem with. Sometimes the responses are quite long-winded! There is the constant proviso that AI can make mistakes; sometimes, its apparent verbosity can appear overconfident. At one point, it asked, “Let me know if you want this change directly committed to your project, or have further optimization questions!” We wish we had that sort of enthusiasm! We think that these applications are where the AI Assistant will be useful. Attempting to manually generate the necessary commands from the register bit fields in the datasheet can be tedious and error-prone, while the November 2026  61 AI Assistant can streamline it. It also seems handy at generating things like bulky or repetitive code. The code that was generated appeared to be well-formatted with detailed comments, so could be used to improve code readability. The AI Assistant was also helpful when we had questions about the VS Code environment and could even access data sheets and project configuration files to respond to queries. Other notes Just like MPLAB X IDE, there is an MCC (MPLAB Code Configurator) extension for VS Code. We don’t use MCC much for our projects since we have specific library files and drivers that we use, so we did not have much need to test it out. We could not easily find a way to install and check tool (programmer) packs and DFPs (device family packs). These are the software profiles that are necessary to work with specific programmers (such as PICkits) or microcontroller families. It appears that the DFPs are automatically installed if needed when a new project is created. Quite a bit of automatic downloading occurred, so we could not easily see how much storage space various features required. Otherwise, packs that are installed through the MPLAB X IDE are automatically detected in VS Code. We observed that some of the extensions have notes that “Features and functionality will remain in active development”, so it appears that the MPLAB Extensions environment is still not complete, at least compared to MPLAB X IDE. We also could not find (within MPLAB Extensions for VS Code) a tool for setting up configuration fuses or viewing memory contents, except for individual variable watches in a debugging session. These aren’t things that we need often, but are invaluable when they are available. XC8 compiler 4.00 While we were writing this article, we saw that version 4.00 of the XC8 Compiler had been released. The notes for XC8 also mention improvements relating to debugging support for assembly code and improved tools and diagnostics. The changelog doesn’t indicate any fundamental changes, but the note that XC8 has now “Removed license restrictions for optimization features” is quite an understatement! Why do we use so many PICs? You may be wondering why we use so many PICs in our projects. Why not an Atmel AVR chip, an STM32 from ST Micro, an NXP microcontroller, or something else? We do sometimes publish projects using those other chips and many of them work well enough. While Microchip Technology advertises in the magazine, that isn’t contingent on us using their devices. The reason is partly historical. We’ve used PICs for decades and have lots of experience with them. However, it’s mainly because we like working with them. A given PIC may not be the fastest chip or the best in every way, but there are a few things they do consistently well. They’re often inexpensive, with more flash and RAM than similarly priced competing chips. That means we don’t have to stress so much about making our program fit. They’re also pretty easy to program once you have the hardware, which will work with just about any PIC. Jumping from an 8-bit PIC to a 16-bit or 32-bit device takes very little effort. Plus, Microchip offers a wide range of devices, from tiny and cheap to big and powerful. We also find that the some aspects of PIC programming (such as the configuration bits) are simple and elegant. We are currently producing an article comparing 8-bit PIC and AVR parts and their configuration bits, which are handled quite differently. Importantly, we only need a small range of hardware to make the pre-programmed microcontrollers we sell in our Online Shop. PICs also tend to have excellent peripherals, many of which can be mapped to different pins. That includes things like PWM, hardware serial, good ADCs, DACs, comparators, programmable logic blocks and more. Other micros have those things too, but some we’ve tried had pretty sparse peripherals, limiting what we could do. In addition to PICs, we have also used Raspberry Pi Picos in a few projects as they have some great features too. We have also been impressed with some of the features of the STM32 chips Andrew Levido has used in his projects; we could imagine using those one day as well. 62 Silicon Chip Australia's electronics magazine This effectively means that the previously PRO level optimisations (which could only be accessed with a paid licence) are now free to all users. This applies to all XC compilers and now makes the -O3 (optimise favouring speed) and -Os (optimise favouring size) options for the XC8 compiler available at no cost. Most of our projects have deliberately avoided the PRO level optimisations so that our readers do not need to pay for a licence to compile our code, although there have been a handful of cases where this has been necessary. Fig.8 shows the Compiler section of the Project Properties under VS Code. While the higher (“3” and “s”) optimisations are available for selection in earlier versions, they will fail on older compiler versions, since these still implement the licence checks that have been removed from XC8 version 4.00. New chips It has been a while since we last reviewed a new family of Microchip microcontrollers. We investigated the PIC16F181xx family of parts (along with some others) in October 2022 (siliconchip.au/Article/15505). Since then, we have used the 20-pin PIC16F18146 in many projects. For projects where smaller chips have been required, we have also used the 14-pin PIC16F18126 and the 8-pin PIC16F18115. These have many handy analog features, including an 8-bit DAC (digital-to-analog converter) and a 12-bit ADC (analog-to-digital converter), as well as many digital peripherals. We noticed the introduction of the PIC16F131xx family of parts a few years ago but did not have the opportunity to do much with them at the time. This family of chips includes a CLB (configurable logic block) peripheral. The PIC16F132xx family has just been released, and it too includes the CLB peripheral. CLB Previously, we have used the CLC (configurable logic cell) peripheral that is featured in the PIC16F181xx family. The CLC can be used to set up logic that can operate independently of the core processor. The CLC could be considered equivalent to adding one or two simple logic ICs, such as logic gates or perhaps a latch, to a microcontroller. siliconchip.com.au For example, it can be used to mix the outputs of two peripherals to generate signals that cannot be directly created by existing peripherals. Nicholas Vinen’s RGB LED Star from December 2025 (siliconchip.au/ Article/19372) used the CLC to create waveforms to control WS2812-based LEDs. This combined a PWM signal with an SPI signal to suit the specific timing needed for these chips. The CLB has some similarities in that it can be used to combine peripherals via logic to work with unusual signals. However, it is much more advanced and is more like a CPLD (complex programmable logic device) than a simple logic chip. So it can emulate much more complex logic. The CLB is based on a unit known as a BLE (basic logic element), seen in Fig.9. There are 32 BLEs available in all PIC16F131xx and PIC16F132xx parts. Each BLE incorporates a four-­ input LUT (look-up table) to provide combinatorial logic, plus a latch to allow sequential logic, such as shift registers. Building blocks like these BLEs are common to many programmable logic devices, including FPGAs (field-­ programmable gate arrays). There are some project examples using the CLB at https://mplab-discover.microchip. com/v2?dsl=clb Unlike other peripherals, the CLB requires a substantial amount of data to be initialised. Each of the 32 LUTs requires 16 bits of data to determine the LUT output for each of the 16 combinations of four bits at its input. There are also bits that determine where the inputs and outputs are routed so that complex logic can be developed from connecting multiple BLEs. Many peripherals might have a handful of byte-sized registers to set up, while the complexity of the CLB requires its registers to be supplemented by an entirely different system. Complex programmable devices store their data in a so-called bitstream, and it is the way this bitstream is loaded that is unusual. The PIC16F13xxx (PIC16F131xx and PIC16F132xx) parts also include a CRC (cyclic redundancy check) memory scanner that can scan through the non-volatile flash memory and confirm (using a CRC code) that the memory has not been modified or corrupted. The CRC peripheral has an alternative mode that can scan a part of flash siliconchip.com.au Fig.8: recent versions of the XC compilers allow use of the “3” (-O3) and “s” (-Os) options that were previously restricted to paid PRO licence holders. Fig.9: the CLB peripheral on the PIC16F132xx family contains 32 of the BLE blocks seen here. The LUT can be used to make combinational logic (including AND, OR, NOT, XOR gates), while the latch can be used for sequential logic, such as memory and shift registers. memory and transfer the contents to the hidden registers that configure the bitstream of the CLB. So this step is used to load the bitstream from non-volatile flash memory into the working memory of the CLB. In a typical application, the on-chip firmware would perform a bitstream load sequence and set up any I/O pins or internal peripherals to connect to the CLB. Finally, the processor would activate the CLB peripheral so that it is active. The PIC16F132xx parts also have the ability to load the bitstream at startup and then halt the processor, effectively becoming a pure logic device. Generating the bitstream There are some handy tools available to turn a conceptual design into a functional bitstream, including a user Australia's electronics magazine interface that can be used to lay out logic elements in a graphical fashion and then synthesise a design into a bitstream. The tool can be found at https:// logic.microchip.com/clbsynthesizer Fig.10 shows the tool editing a 12-bit linear feedback shift register (LFSR), which can be used to generate pseudo-­ random values. It has no inputs and the eight most significant bits are available as outputs. The OR gates are necessary to trap the all-zeroes state that might otherwise cause the LFSR to latch up. The outputs can be mapped to different pins via the PPS (peripheral pin selection) module. The synthesis tool requires internet access, since Microchip’s servers host the software that is needed. Internally, the tool uses the Verilog HDL (hardware description language) and modules can be created with snippets of Verilog. The open-source Yosys November 2026  63 Fig.10: you can try out the CLB Synthesiser tool on the Microchip website, even if you don’t have an IDE installed. The design shown here implements a 12-bit LFSR (linear feedback shift register) that can generate pseudo-random data. framework is used for digital logic synthesis. The bitstream download also includes other synthesis files and some C code to initialise the CLB. There have been some efforts to analyse and provide alternative means to generate the bitstream. You can see one project at https://mcp-clb.markomo.me Other features This family also includes a 10-bit DAC. We’ve found the 8-bit DAC on the PIC16F181xx family quite handy, so we may investigate this family further for future use. The CLB feature is also available on PIC16F131xx parts, as we noted earlier. The first members of the PIC16F132xx family were the larger (28-, 40- and 44-pin) chips, which may be useful in the case of projects that require microcontrollers with more I/O pins. We have recently seen the announcement of 8-pin, 14-pin and 20-pin parts in this family. The PIC18-Q35 family also includes CLB peripherals. PIC18 parts have an 8-bit processor, like the PIC16 parts, but are generally more powerful. Interestingly, the CLB in these parts has 128 BLEs, so they can implement even more complex logic. The CLB is certainly a fascinating peripheral, and we can see that it has a lot of potential. The larger parts may 64 Silicon Chip be handy if we need more I/O pins for a project. Concepts like LED and switch matrix scanning with many I/O pins are likely to be well-suited to handling by CLB logic. So far, we have not found a compelling project use for the CLB peripheral. With the recent release of 20-pin parts in this family, we may see the likes of the PIC16F13246 as a drop-in successor to the PIC16F18146 that we have used so often. PDID PDID stands for Programming and Debugging Interface Disable. As the name suggests, it can be used to lock down the programming interface, preventing programming, debugging and erasure of the chip. This feature is present on the PIC16F132xx family of microcontrollers and is set by the ICSPDIS configuration bit. Crucially, once the ICSPDIS bit has been enabled, it cannot be disabled and the device cannot be reprogrammed by an external programmer or debugging tool. It is clearly intended to be a security measure to prevent firmware tampering. Of course, this feature should be treated with absolute care, since it cannot be disabled. Interestingly, these parts still allow other methods for modifying their flash memory, so it is possible to allow Australia's electronics magazine firmware updates. The internal NVM (non-volatile memory) controller can write to flash memory, and thus the firmware can implement a bootloader to allow updates. But that can only occur if the firmware has been written to allow this. Conclusion With the Raspberry Pi Pico Extension for VS Code being the official way to use the Pico C SDK, we expect that we will be using VS Code more as time goes on. The MPLAB Extension for VS Code IDE looks to be very useful, although it appears that some features present in MPLAB X IDE are not yet available in VS Code. For now, we will use both the MPLAB X IDE and VS Code for PIC programming. Having both installed will also streamline the addition of tool packs and device family packs. One thing we like about the VS Code IDE for Microchip devices is that it’s quite a bit faster than MPLAB X IDE as it does not rely on Java. We found the AI Assistant to be helpful in many cases. It even has the ability to make changes directly to code, so it would be entirely possible to write the bulk of a project through AI prompts only. Like many AI implementations, the AI Assistant is not perfect and can make mistakes, so it is a tool that SC should be used with care. siliconchip.com.au