PIC microcontrollers are one of the industry's leading MCUs. These MCUs can be programmed by simple serial interface. There are lots of circuits and programs available on the internet to program PICs. I have made a simple circuit that could program most of the PIC MCUs that support serial programming.  I have successfully used this programmer on a PIC16F877A and PIC18F4550. I believe it should work for other PICs as well.

Here is a picture of my serial programmer. Note that the circuit is hidden inside the connector shell. This is very compact and easy to use. Note that the programmer circuit uses power from the target hardware.

Following is the schematic of the serial programmer.

Layout - Top & Bottom layers

Download the schematics and layout files for the serial programmer here

You can use most of the serial programming applications that supports JDM2 cable. I use Winpic programming software. 

How to user this programmer:

1, Hook up the DB9 female connector to your PC's serial port

2, Hook up the pig-tail end to the target hardware (the PIC microcontroller). Connect the following signals to your target MCU.

3, Invoke the Winpic programming software and initialize the interface. Make sure to select the "JDM (2) for serial port" option in the interface type.

4, Once the interface initialization is successful, select the right device (your MCU number) from the device menu.

5, Now, you can load the .hex file and program the device. Configuration word, ID words and data memory can also be programmed.