Oric Telestrat-specific information for cc65


An overview over the Telestrat (Telemon 3.0 : http://orix.oric.org) runtime system as it is implemented for the cc65 C compiler.)

1. Overview

2. Binary format

3. Memory layout

4. Platform-specific header files

5. Loadable drivers

6. Limitations

7. Other hints

8. License

1. Overview

This file contains an overview of the Telestrat runtime system as it comes with the cc65 C compiler. It describes the memory layout, Telestrat-specific header files, available drivers, and any pitfalls specific to that platform.

Please note that Telestrat-specific functions are just mentioned here, they are described in detail in the separate function reference. Even functions marked as "platform dependent" may be available on more than one platform. Please see the function reference for more information.

2. Binary format

The standard binary output format generated the linker for the Telestrat target is a machine language program with a 20 bytes header described here : http://orix.oric.org/doku.php?id=orix:header

This header is used for Telemon 3.0.

Anyway, for Telemon 2.4, there is no file management, there is no TAPE routine in Telemon, there is no way to load a binary easily.

Stratsed (the Telestrat operating system) handles files management. Stratsed is loaded to memory from floppy disk.

There is no tool to insert a binary in a Stratsed floppy disk.

The only way to load a binary (for Telemon 2.4) is to :

Please note also, that the binary converted into TAP file, will not produce a right stratsed file when tap2dsk and old2mfm are used. You will be in the case that Telestrat/Stratsed crashed when you do "DIR" command.

If you know the Stratsed disk format, please contact the author of this doc.

3. Memory layout

In the standard setup, cc65-generated programs use the memory from $0801 to $9800; so, nearly 37K of memory (including the stack) is available. ROM calls are possible without further precautions.

Special locations:


The C runtime stack is located at $97FF (or $B3FF), and grows downwards.


The C heap is located at the end of the program, and grows towards the C runtime stack.

4. Platform-specific header files

Programs containing Telestrat -specific code may use the telestrat.h header file.

4.1 Telestrat-specific functions

The functions listed below are special for the Telestrat. See the function reference for declaration and usage.

4.2 Hardware access

The following pseudo variables declared in the telestrat.h header file do allow access to hardware located in the address space. Some variables are structures; accessing the struct fields will access the chip registers.


Access to the VIA (Versatile Interface Adapter) chip is available via the VIA variable. The structure behind this variable is explained in _6522.h.

5. Loadable drivers

5.1 Extended memory drivers

No extended memory drivers are currently available for the Telestrat.

5.2 Joystick drivers

telemon 2.4 & 3.0 manages joysticks but it had been handled yet.

5.3 Mouse drivers

Telestrat manages also mouse, but it had been no handled yet in this version.

5.4 RS232 device drivers

Telestrat has a RS232 port, but it's not used

6. Limitations

6.1 Disk I/O

Telemon 3.0 handles fopen, fread, fclose primitives. It means that this function will crash the Telestrat because Telemon 2.4 does not have these primitives. By the way, Telemon 3.0 uses an extension "ch376 card" which handles sdcard and FAT 32 usb key. In the next version of Telemon, FT DOS, Sedoric, Stratsed will be handled in these 3 primitives (fopen, fread, fclose).

7. Other hints

8. License

This software is provided 'as-is', without any expressed or implied warranty. In no event will the authors be held liable for any damages arising from the use of this software.

Permission is granted to anyone to use this software for any purpose, including commercial applications, and to alter it and redistribute it freely, subject to the following restrictions:

  1. The origin of this software must not be misrepresented; you must not claim that you wrote the original software. If you use this software in a product, an acknowledgment in the product documentation would be appreciated but is not required.
  2. Altered source versions must be plainly marked as such, and must not be misrepresented as being the original software.
  3. This notice may not be removed or altered from any source distribution.