about burning program in flash memory

[Dilpreet Singh]

when a chip of microcontroller is manufactured in fab then its flash memory is comletly empty then how a burner access its flash memory as there is no boot loader when chip is formed then how first program is transfer to microcontroller. ?

 

[betwixt]

Most MCU's have a hardware programming circuit built in to them. You activate it with a specfic sequence of voltages and data. When in programming mode, the hardware takes care of the flash addressing and write operations so no bootloader is needed.

Brian.

 

[Dilpreet Singh]

IS hardware programming circuit built in to ATMEGA8 ?

 

[betwixt]

To be honest I have never used one but I think all MCUs with internal memory have a hardware interface. I can't see how they can be used otherwise. More modern ones use low voltage programming where serial commands and data can be entered through dedicated pins, older ones used high voltage programming and data was presented in parallel across several pins.

Brian.

 

[Easyrider83]

Read about ICSP programming. ATMEGA using SPI interface, STM8 using SWIM, STM32 JTAG/SWD and e.t.c.