If you single step with irq1.com (and procede int 21) it hangs the system.
But if you run it outside debug it works okay.
section 1 of 1 of file irq1.com  
begin 644 irq1.com
1Y"$D_>L`ZP#K`.8AN`!,S2'Z
`
end
sum -r/size 2765/51 section (from "begin" to "end")
sum -r/size 57017/17 entire input file
--- Renegade v5-11 Exp
---------------