FreedomStudio: how to enter an Assembler program to be uploaded in hifive1-revb board

I have acquired a hifive1-revb board, and I am trying to use it with FreedomStudio. I can run examples like hello and welcome, and they work ok even though I don’t understand the details why they work. I have an example, written in assembler, that works ok using VisualStudio Code tool with PlatformIO extension. I am looking for help for entering an assembler program in FreedomStudio. I haven’t seen any tutorial or something about. Thanks and regards.
Francisco Rivera.

Hi, I am a newbie to risc-v world. I’ve found the free JLink tools to be useful by using the “r” (reset) cmd and following the instructions that the Hifive executes after the reset occurs. You can also set breakpoints to stop at certain points, “s #” will step thru # instructions, type “regs” to see a register dump, JLink does not seem to display the fp regs.

JLink has a “savebin” cmd which loads machine code into a memory location. You could use the risc-v assembler to compile some assembly code and then use the JLink savebin cmd to load the code into the boards flash memory. You could then trace the code execution.

When you create a Freedom E SDK project it uses the Sifive Freedom Metal library by default: Documentation for this is at

This “bare metal” environment allows you to do many interesting things such as connecting the board to a computer and then having the board send out information via the serial ports its exposes using the usb port.