Raymond Sills via Groups.Io wrote:
Hi Guys:Tom Pittman's original Tiny BASIC was 2K bytes, but it did *not* include the I/O drivers. It just had three LBR's (CONIN, CONOUT, and BREAK), which you had to patch to point to your system's I/O drivers.
On an Elf with one of RCA's monitors (i.e. UT4), or a Quest or Netronics Elf with their monitors, you had to provide your own I/O routines. These vectors were then patched to jump to your routines. They would of course be different for every system, as there were no standards in those days. It might use Q and EF3 or EF4, a parallel port, an actual UART chip, an 1861 video chip, etc.
Tom provided detailed instructions for modifying Tiny BASIC. When the system had extra features (like an 1861 video chip), then people extended Tiny BASIC to add commands to control it. The RCA VIP, Netronics, and Quest Elves all did this.
You're generally going to download a "package" that comes with somebody's hardware-specific I/O routines already included. To work, your Elf needs to have the *same* hardware setup. Or, you have to change it to support the hardware you have.
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