7/27/2019 Avr Isp Programmer

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AVR ISP PROGRAMMER

Since Atmega8 is In-System-Programmable (ISP), flash memory of Atmega8 can be

programmed In System through SPI interface. We can download our data serially into

Atmega8 using a simple AVR ISP programmer & Ponyprog2000.

Fig.2.8 ISP Programmer

Output of serial port of PC is -12 V to +12 V which will be harmful for controller. So, the

zener diodes (voltage regulator) are used. They limit +15V to +4.7V and -15V to -1V.

Internal pull up resistors are provided at the (~RESET) pin and if nothing is connected to thispin, the micro controller tries to execute the program written within it. We can provide a

resistance capacitance reset circuit, but its not always necessary.