Hi all, I came across few programmer schematics and noticed that the microcontroller used to store firmware is the same product as the microcontroller that is intended to programmer.
My question is, how are we going to do the 1st time programming to the firmware microcontroller? is it like chiken and egg?
Thank you.
This is, of course, the fundamental flaw in building your own programmer!
You will need to beg, borrow or hire a programmer to program you first chip; or see if the chip can be purchased ready-programmed; or find a service that will program chips for you.
But do note that there are plenty of chips these days that don't need a programmer at all - why not just use one of them?
Some chips can be programmed in multiple ways. One way may be using a serial interface (maybe UART or SPI or JTAG) with/or without an internal boot loader. One way may be a high-voltage parallel programming mode that may allow update of boot loaders or erase of protection bits that are not accessible using the serial update methods.
You will have to supply more information. The _exact_ name of the processor and preferably a link to the programmer if you want a better answer.