Setting string register from Karel

I want to change string register value from Karel.

Similar to what is written in manual for setting numeric registers, I tried for string register:

SET_VAR (entry, '\\mhrob01\*strreg*', '$STRREG[1]', '1', STATUS)

Command is not working (it's not working for numeric registers also).

What 'mhrob01' stands for? I there another way?

Thanks,

Its working now. I simply don't have this built in functions in my manual (for R-30iA).

I have to get a new one