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Texas Instruments TI-99/4A Mystery Cache

Hidden : 3/25/2015
Difficulty:
3.5 out of 5
Terrain:
1.5 out of 5

Size: Size:   micro (micro)

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Geocache Description:


The Texas Instruments TI-99/4A was the first home computer with a 16bit processor, and that was in 1979.


The TI-99/4A was also the first computer that I had as a child. It was also the computer that I learned how to program on. I remember copying code from the back of magazines line by line so that I could play a game. The game I remember most vividly was Burger Time. It wasn't available on a cartridge for TI, so I had to program it in and then save it to a cassette tape.

The TI 99/4A did not have a bitmap graphic or sprite graphic command available in TI BASIC. The only way to create graphics was to remap the existing character set with the image you wanted displayed. Each character consisted of an 8x8 grid.

The code segment below, if typed into a functioning TI-99/4A will display the coordinates of where the log is hidden. There are many ways to solve this without running the code.

The cache is not located at the posted coordinates

110 CALL CLEAR
120 CALL CHAR(65,"003C040820202000")
130 CALL CHAR(66,"0018242424241800")
140 CALL CHAR(67,"003C02023C407E00")
150 CALL CHAR(68,"001824241C042418")
160 CALL CHAR(69,"003C040810101000")
170 CALL CHAR(70,"001824241C042418")
180 CALL CHAR(71,"0018242424241800")
190 CALL CHAR(72,"0008180808083E00")
200 LET A=6
210 LET B=7
220 LET C=4
230 LET D=5
240 LET E=7
250 LET F=5
260 LET G=1
270 LET H=7
280 PRINT "N 44 4A.BCD W068 4E.FGH"
290 FOR T=1 TO 1000
300 NEXT T



Beginners Basic Manual

You can check your answers for this puzzle on GeoChecker.com.

Additional Hints (Decrypt)

N xabjyrqtr bs NFPVV, Ovanel naq Urknqrpvzny znl uryc...

Decryption Key

A|B|C|D|E|F|G|H|I|J|K|L|M
-------------------------
N|O|P|Q|R|S|T|U|V|W|X|Y|Z

(letter above equals below, and vice versa)