NitrOS-9 ROM Kit FAQ

Q. What is the the NitrOS-9 ROM Kit?

A. The NitrOS-9 ROM Kit is a software package for the NitrOS-9 operating system that allow the CoCo to be used in embedded applications. These are applications that might require the Color Computer to be run in adverse conditions or with physical and power constraints. For those who want to use NitrOS-9 as a basis for their applications but want to run in such a curtailed environment, the NitrOS-9 ROM Kit is perfect because it contains NitrOS-9 modules that eliminate the need for a disk drive.

Q. What can I do with a NitrOS-9 ROMMED CoCo?

A. There many applications which can use such a setup. Imagine a CoCo which, when turned on, starts sampling temperature and environmental information from its A/D joystick ports or through a special hardware card connected to the cartridge port. Or a CoCo as a terminal interface, hooked up through its serial port to display some real-time data gathered from another system. Any application which requires near-instant startup times and no external storage is probably a good candidate for using NitrOS-9 in ROM.

Q. Where does the ROM go?  In the cartridge port?

A. No. The ROM actually replaces your CoCo's BASIC ROM. On a CoCo 1 and 2 this can be one 24- or 28-pin ROM chip, or even two 24-pin ROM chips. In either case, only 16K of ROM is available for both OS-9 and programs. In a CoCo 3, however, the 28-pin ROM chip is 32K, allowing for even more space.

Depending on the CoCo, you will almost certainly have to desolder and remove the existing ROM chip, and replace it with a socket in order to use your ROM application.

Q. How big can my application be in ROM?

A. It depends on which version of NitrOS-9 you are using. On NitrOS-9 Level 1 on a CoCo 1/2, you have 16K of ROM space, most of which is devoted to the kernel andother system modules. If you are conservative with your module list, you can get around 3 or 4K for your application.  This doesn't sound like much, but for small, assembly programs it's more than enough.

For NitrOS-9 Level 2 on a CoCo 3, there is 32K of ROM available, though the NitrOS-9 modules are slightly larger. Still, with a conservative ROM boot file, your application can have around 12K of space to reside in.

Q. Do NitrOS-9 and the applications actually run in ROM?

A. No. The NitrOS-9 ROM Kit contains modules which cleverly copy the contents of ROM to appropriate places in RAM, so the NitrOS-9 kernel, its modules and your application are actually residing in RAM when they are executing.