Gold Miner For TI-99/4A
Dig your way into the Lost Mine and search for gold in this exciting TI-99/4A translation of a game first published in COMPUTE!, July 1982.
"Gold Miner" will run in TI BASIC, using about 5K. It won't run in Extended BASIC because of the character definition using ASCII 144 and above.
Most of the program was translated quite easily from Joseph Weber's original VIC-20 version except for formatting the display of the score and the charges. Extended BASIC contains commands to display at any position on the screen. But TI BASIC will print only at the bottom of the screen, which scrolls the whole display up. Since I wanted this program to run in TI BASIC, I had to use string manipulation to format the score and charges using their ASCII representations. Then, using HCHAR, printing at specific screen locations was possible without disturbing the rest of the display (see lines 1450-1640).
The only other modification is to the main character. I designed a small pick-ax to represent the miner, and animated it, so it would seem to chop its way into the mine. This is done in the main loop, lines 640 - 660, and slows execution only slightly. But it doesn't matter in this game because speed is unimportant. In fact, you can walk away from the game, come back an hour later, and take up where you left off.
Digging for golden nuggets in the TI version of "Goldminer"
One other point: You must hold down the key, joystick, or fire button until the program calls the routine to read the input. It makes the joystick a bit awkward, but this doesn't affect the game because reflex time is unimportant with "Gold Miner."