25-kgog-tv-satellite-uplink

25: KGOG-TV (Satellite Uplink)

Instructions

Align the satellite dish with the target satellite by setting the azimuth, elevation, and frequency. Then transmit the data from EMBER-2's video (file 301) after encrypting it using the TV station's encryption key (file 199).

The azimuth, elevation, and frequency of the target satellite are available in file 300.

Note that you must align the satellite dish before transmitting any data.

For more information see "Look to the Stars with Satellite Uplink Systems" in the second issue of the zine.

Solution

XA (global)

; MOVE MOTR
GRAB 300
LINK 800
LINK 799

SEEK 5
COPY F #FREQ

SEEK -5
COPY F X
REPL AZIM

SEEK 1
COPY F X
REPL ELEV

WIPE
HALT

MARK ELEV
LINK 801
TEST #ELEV < X
TJMP ELEV_LESS
SUBI #ELEV X T
COPY -1 X
JUMP LOOP
MARK ELEV_LESS
SUBI X #ELEV T
COPY 1 X
JUMP LOOP

MARK AZIM
LINK 800
TEST #AZIM < X
TJMP AZIM_LESS
SUBI #AZIM X T
COPY -1 X
JUMP LOOP
MARK AZIM_LESS
SUBI X #AZIM T
COPY 1 X

MARK LOOP
FJMP END
SUBI T 1 T
COPY X #MOTR
JUMP LOOP

MARK END
COPY 1 M

XB (global)

; TRANSMIT
GRAB 301
SEEK 1
LINK 800

; WAIT FOR MOTR
VOID M
VOID M

REPL BROADCAST_KEY

LINK 799

; ENCRYPT
MARK ENCRYPT_LOOP
COPY 1 M
COPY M X

SUBI 9999 X T
TEST F > T
TJMP ENCRYPT_WRAP

SEEK -1
ADDI X F #DATA

MARK ENCRYPT_LOOP_END
TEST EOF
FJMP ENCRYPT_LOOP

COPY -1 M
WIPE
HALT

MARK ENCRYPT_WRAP
SEEK -1
SUBI 9999 X T
SUBI F T T
SUBI T 1 #DATA
JUMP ENCRYPT_LOOP_END


; BROADCAST
MARK BROADCAST_KEY
GRAB 199

MARK BROADCAST_LOOP
TEST M = -1
TJMP BROADCAST_END
COPY F M
TEST EOF
FJMP BROADCAST_LOOP

SEEK -9999
JUMP BROADCAST_LOOP

MARK BROADCAST_END

Results

Cycles	Size	Activity
502	79	6