USBasp is a USB in-circuit programmer for Atmel AVR controllers. It simply consists of an ATMega48 or an ATMega8 and a couple of passive components. The programmer uses a firmware-only USB driver, no special USB controller is needed.
Features

• Works under multiple platforms. Linux, Mac OS X and Windows are tested.
• No special controllers or smd components are needed.
• Programming speed is up to 5kBytes/sec.
• SCK option to support targets with low clock speed (< 1,5MHz).
• Planned: serial interface to target (e.g. for debugging).

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AVRUSBBoot is a bootloader for the Atmel AVR controllers. It uses a firmware-only USB driver to transfer binary data from the PC to the flash of the controller. Once the AVR is flashed with the bootloader, no other ISP programmer is needed; then the microcontroller can be reprogrammed over USB.
Features

• Software works under multiple platforms. Linux, Mac OS X and Windows are tested.
• Tested with ATMega8-16
• No special USB controllers or smd components are needed.
• Bootloader fits into 1024 word bootloader block

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Batwatch is a simple monitor for a solar panel battery charger, using an Atmel ATtiny13V. It periodically measures the charge current and battery voltage, and shows them by blinking two LEDs. The circuit built into the plug of a VW solar charger panel that is used to prevent a discharge of the battery when a car is not used for some time. A modern car contains a large amount of electronics, and a quiescent current of 40-50mA .source

Annother method to time parachute ejection is a timer.This is Rocketry Timers based on AT90S2323.

• Processor: AT90S2323
• Size: 76mm x 25mm
• Programming language: Assembler

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This Altimeter used for measurement during a rocket flight, this altimeter reads barometric data and stores it 10 times per second in an 8K EEPROM until apogee is detected (when pressure starts to rise again). Then a MOSFET output is activated to trigger a pyrotechnic ejection charge for a parachute. An optional second channel can be used for dual recovery (small drogue first and main parachute later for soft landing without too much drift).

• Processor: AT90S2323
• ADC: TLV1541 or TLV1544 (10 bit ADC 1 or 4 channels)
• Sensor(s): MPX5100 (barometric)
• Schematics
• Programming language: Assembler

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