USB Bootloader

Posted on Feb 6, 2014

The bootloader can be used for the all USB PIC devices (PIC18F4550, PIC18F4455, PIC18F2550, PIC18F2455, PIC18F4553, PIC18F4458, PIC18F2553, PIC18F2458). Since the bootloader is designed for the Microchip demo board, the configurationof the bootloader possibly will not fit for your project. E. g. you want to use another pin for bootloader mode entry or you do not want to spend 4 pins/LED`s

Click here to download the full size of the above Circuit.

for displaying the current status. Fortunately, the source code of the bootloader firmware is available. It is written in C language. It can be compiled with Microchip`s C18-Compiler, even with the free version of the compiler. In the directory USB Device - BootloadersVendor Class - MCHPUSB BootloaderBootloader - Firmware for PIC18F4550 Family Devices you find the project file MCHPUSB. mcp which has to be opened with MPLAB. In the project file the path settings point to the default C18 compiler directory c:mcc18. If you have installed the compiler in a different directroy, you have to modify the path settings in MPLAB. To do this, select "Project - Build options - Project" from the MPLAB menu after opening the project file MCHPUSB. mcp. In this dialog go into the "Directories" tab and change the modify the Now you can build the project via "Project - Build All". If you use the free version of the C18 compiler, the linker will fail since the generated code exceeds the boot block size. To fit the bootloader into the bootblock, we can stirp unnecessary functions from the source code, like code for showing the status of the bootloader via 4 different LEDs. Here the code parts which can be removed without loosing bootloader functionality:. /* P R I V A T E P R O T O T Y P E S */ -> remove prototype //void BlinkUSBStatus(void);. . . void BootService(void) { -> remove call to BlinkUSBStatus //BlinkUSBStatus(); if(usb_device_state...

Visit page

Leave Comment

characters left:

Related Circuits

2000 Chevrolet Chevy Blazer Wiring Diagram

The Part of 2000 Chevrolet Chevy Blazer Wiring Diagram: power distribution schematic, fuel pump relay control, fuel pump and sender, splice pack, fuel pump prime connector, ground distribution...

Controlling a Mazda Car Using an iPhone

This hack illustrates how a car can be controlled from anywhere in the world by tapping into the disgnostic systems and onboard webserver of the car. The objective is to keep the car live and...

Low Frequency Sine wave Generators Schematic

The two circuits below illustrate generating low frequency sine waves by shifting the phase of the signal through an RC network so that oscillation occurs where the total phase shift is 360...

Simple Indicator for Dynamic Limiter Schematic Diagram

The indicator described here is specifically designed for adjusting the dynamic limiter described elsewhere in this edition and checking whether the maximum level of the reference voltage (P1)...

a d converter

This is the first draft of the pH to 1-Wire converter schematic, and some of the component values are still missing. The original circuit runs on 12 VDC, but since the A/D converter IC must be...

NSLU2

Aquaponics systems need a good water quality, and one of the parameters is pH value, which needs to be within a certain range in order for the fish and plants to thrive. This is of course also true...

Thermal Watt Converter Test Circuit Schematic

AC Wiring Diagram

New Circuits

Zero consumption Anti-theft High power Code Switch for E-Bike Batteries

This project fits more for custom made battery casing that can have more space to hide things inside. This switch with few alterations can be used for any other project as well but is designed based on e-bike needs! This project use a clever functionality of....
Ultrasonic distance finder circuit

The circuit described here uses ultrasonic oscillations and operates based on the propagation velocity of these oscillations in the air. Thus, we can easily determine the distance of two points if the time within which the wave travels this distance is....
Simple Metal detector circuit with CD4030

Sometimes the precious metals are hidden too deep and are not detected except with complicated devices. In many cases, however, small pieces of precious metal buried near the surface can be detected by relatively simple means. Everyone is very attractive to....
Fully automatic watering circuit for flower pots

Many times for various reasons we forget or can not water the plants that we have in our homes. And many humidity sensors units just notify us with a beeping sound or with a flashing light, that the pot needs watering. But what if we are away from home? This....
Simple deep searching metal detector circuit

The principle behind a metal detector is really very simple. Proof of this is the circuit that follows, in which it proves that the construction of a metal detector can be done in the minute, with few components that we find very easily everywhere. With the....
Sub-Harmonic Bass Converter for Electric Guitars

The sub-harmonic bass generator is a sound producing unit for guitars. The sound it produces looks very much like that of the bass guitar. The octave generator is sometimes quite unusual since it does not produce any of the usual ways of coloring the sound,....
Echo Depth Sounding Sonar for Boats

In the past the sounding (sea bottom measurement) was done with the "bullet", that is, with a heavy lead object that the seamen plucked into the sea hung from a calibrated rope. As soon as the "bullet" reached the bottom, the depth appeared directly from the....
100W HiFi Audio Amplifier Circuit

This Amplifier was designed to have the following specifications: Distortion less than 0.1% at full power of 100W even at 20KHz. Power has to be attributed to an extended bandwidth. The output transistors must be protected against short circuits. The power....
Plant-Pot Water Level Indicator Circuit

A series of LEDs serve to alert the gardener when plants need water. Using two conventional digital integrated LEDs and a series of LEDs, we make a very useful device for gardening. The device detects the amount of water in the pot and alerts the grower.....

Create NOW your QR MENU for your Restaurant / Hotel / Bar / Caffe,

Comprehensive ordering/paying features. fully personalized to suit your Business.

Update Anytime! Easy and Simple!

Popular Circuits

Dynamic to electret microphone circuit

This is a simple microphone preamplifier circuit which you can use between your dynamic...

Light isolated solid state power relay circuits

Both circuits use the GE. SC146B, 200 V, 10 A Triac as load current contacts. These triacs are...

Breath-alert-alcohol-tester

When power is applied to the circuit, the heater coil in the sensor is energized by the 5-V...

Large Lcd Display Buffering Driver Circuit

Large LCD devices of 1 or more exhibit a large driving capacitance to the driver circuits. To...

10 Watts Mosfet Audio Amplifier

Here is a 10W MOSFET audio amplifier circuit, sound that only requires a single source. Single...

building a gps logger

The user interface will consist of a single button and several LEDs or a RGB LED through which...

Avr32 Uc3b Schematic Checklist

The BA1451F is a Tuner system IC for electronic tuning for AM Radios FM IF, and MPX. It has been...

Discussing Measuring Flash Duration

Here is simple method that you can try. It might NOT be as accurate as scientific professional...

Vibration Alarm Circuit

This alarm can be very useful in a room or an area that should normally have no movement at all...

USB Interface Board Tutorial Using PIC18F4550

This project demonstrates a computer control interface using a USB Board. (USB INTERFACE...

22 Different Brands of 12AX7 Tubes Tested Against Each Other

Today, it is by far the most common preamp tube used for electric guitar amplification and there...

LED Lighting For Dual-Filament Lamps

Before we describe how it`s done, note that we recommend that the result be checked as having...