I've created an IDE for the picoblaze-3 microcontroller (Xilinx TM). The IDE is an open-source project (GPL-license) and works under the Linux operating system.
The IDE supports the following:
- Editor with syntax highlighting,
- Assemble and export to: HEX, VHDL or MEM files,
- Simulate the source code and see/modify the scratchpad, registers and I/O ports.
For those who are interested, checkout: