Saturday, November 24, 2012

12-24v High Current Motor Speed Controller Part 1

 This 12V or 24V high-current DC Motor Speed Controller is rated at up to 40A (continuous) and is suitable for heavy-duty motor applications. All control tasks are monitored by a microcontroller and as a result, the list of features is extensive.

This high-current motor speed controller is based on a PiC16F88 microcontroller. This micro provides all the fancy features, such as battery monitoring, soft-start and speed regulation. it also monitors the speed setting potentiometer and drives a 4-digit display board, which includes two pushbuttons.

The 4-digit display board is optional, but we strongly recommend that you build it, even if you only use it for the initial set-up. it unlocks the full features of the speed controller and allows all settings to be adjusted.

Thursday, November 1, 2012

AVR ISP ScoketBoard

Most Atmel AVR microcontrollers can be programmed via their in-built serial programming interfaces (SPI). This method is ideal for in-situ programming, such as might be used in manufacturing or for firmware development or field upgrades.

In this scenario, the micro remains in its socket on the application board and a low-cost in-system programmer (ISP) is plugged into a dedicated programming header. In other words, the microcontroller does not have to be removed from its socket and plugged into a parallel programmer each time a firmware update is required.

However, in some cases it is desirable to programme a microcontroller stand-alone, such as when the application board is unavailable or doesn’t include an ISP (or JTAG) header. A low-cost method of stand-alone programming might also be useful where a batch of chips is needed for a small prototype run and the cost of a commercial parallel programmer is prohibitive.