Is it possible to send the content of text file over PuTTY over a serial port?
Use Plink (a command-line connection tool from PuTTY suite). It's a console application intended to automate connection tasks, like yours. Being a console application, you can redirect its input from a text file:
plink.exe -serial -sercfg ... < input.txtSee Using the command-line connection tool Plink
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