Thursday, November 25, 2010

Using the PLL on LPC17xx

The Phase Locked Loop is a peripheral on the LPC17xx that can be used to obtain various frequencies from the frequency sources available. It can multiply and divide the reference frequency to obtain a wide range of CPU frequencies. This tutorial describes how PLL0 can be used.

Wednesday, November 17, 2010

Hello Word ( LED blinker ) on LPC1768 explained. GPIO tutorial

Traditionally, blinking an LED has been the first program written for almost any embedded system and LPC1768 is no exception. Here's a detailed description of all the software tools needed to get started. The LPC1768H schematic is available in the NGX website. The schematics show that TEST_LED is connected to P1.29. Now, for the register description, we'll need the LPC1768 manual.

Wednesday, October 20, 2010

USB Bootloader for LPC1768-H Blue Board

The JTAG debugger has been working quite well. But it needs a parallel port which most laptops including my own lack. LPC17xx conveniently supports USB device interface which can be used for bootloading. USB is ubiquitous and using it will obviate the need for any extra programming hardware.

Tuesday, October 12, 2010

Hello World from LPC1768

Finally, the blueboard LPC1768-H arrived. Have a look.

Unfortunately, it did not have accessories like JTAG cable or mini-USB cable. So, a quick visit to the local electronics store was needed. Once the mini-USB cable was plugged into the blueboard, the LED started blinking. Apparently NGX had pre-loaded the board with a test program. Now I had to say "hello world" through the board.

Thursday, October 7, 2010

Hobby work on ARM cortex M3

I've been a staunch follower of AVR 8-bit AtMega series of Microcontrollers for hobby works at home. Working with the AtMega line has been pure fun. But the time has finally come where the power of an AtMega can no longer slake my thirst. The next logical step would be to move to a 32-bit controller. The biggest pain in making the move is the absence of a fantastic community like AVRFreaks.