One Kid's Weerd Journey into Software

Arthur A. Gleckler

One Weird Weerd Game You Can Play on Your TRS-80

One Weird Kid's Weerd Journey into Software

Start screen

COSMAC ELF

From http://www.cosmacelf.com/gallery/netronics-ads/elf-ii-flyer-page-2.html.

Radio Shack catalogs

From http://www.radioshackcatalogs.com/.

User's manual for Level 1

From http://www.trs-80.com/wordpress/manuals-hardware/#model1.

Listings in magazines

CLOAD

SoftSide

80 US

Big Five Software games

From http://www.bigfivesoftware.com/trs80/trs80main.htm.

Microsoft Editor/Assembler Plus

Started

TRS-80 Video Display Worksheet 1

TRS-80 Video Display Worksheet 2

TRS-80 Video Display Worksheet 3

Spaceship Descriptions 1

Spaceship Descriptions 2

Script data

01820 TITLEG  DEFB    23
01840 *LIST OFF
01860         DEFB    6
01880         DEFB    24
01900         DEFB    5
01920         DEFB    25
01940         DEFB    5
01960         DEFB    26
01980         DEFB    4
02000         DEFB    27
02020         DEFB    4
02040         DEFB    28
02060         DEFB    4
02080         DEFB    29
02100         DEFB    4
02120         DEFB    30
02140         DEFB    4
02160         DEFB    31
02180         DEFB    5
02200         DEFB    31
02220         DEFB    6
02240         DEFB    31

Example code

00002 I1      LD      (IX+1),0
00004         LD      (IX+3),0
00006         CALL    VERT
00008         LD      (IX+5),A
00010         LD      (IX+6),0
00012         LD      (IX+7),1
00014         LD      A,(TABLE+8)
00016         AND     1
00018         OR      A
00020         JP      Z,LT1
00022         LD      (IX+0),2
00024         LD      (IX+2),-1
00026         LD      (IX+4),127
00028         RET
00030 LT1     LD      (IX+0),6
00032         LD      (IX+2),1
00034         LD      (IX+4),0
00036         LD      (IX+7),-1
00038         RET

Definitions

00902 EYED    DEFW    00800H
…
00988 SHPTWO  DEFW    00000H
…
00994 SHPTHR  DEFW    00000H
…
01020 SHPFR   DEFW    00000H
…
01058 SHPFIV  DEFW    00000H
…
01092 SHPSIX  DEFW    00000H
…
01130 SLED    DEFW    00500H
…
01192 TREK    DEFW    00300H
…
01276 UGLY    DEFW    00000H
…
01304 DROP    DEFW    00200H

Subroutine to display a message

00220 MESSAG  LD      A,(HL)
00240         CP      '@'
00260         RET     Z
00280         LD      (DE),A
00300         INC     HL
00320         INC     DE
00340         JP      MESSAG

Example displaying a message

01240 CONTIN  DEFM    'PRESS <ENTER> FOR INSTRUCTIONS OR '
01260         DEFM    'PRESS '
01280         DEFB    39
01300         DEFM    'S'
01320         DEFB    39
01340         DEFM    ' TO DISPLAY HISCORES.@'
01360 MESG    DEFM    'PRESS <ENTER> FOR INSTRUCTIONS.@'
01380 BEGIN   CALL    CLEAR
01400         LD      A,25
01420         LD      (COUNT),A
01440         LD      HL,CONTIN
01460         LD      DE,16320
01480         CALL    MESSAG

Demo

Cassette player

OODA Loop

Perhaps sketch out some code on paper.

Code sketch

OODA Loop

Perhaps sketch out some code on paper.

Load Microsoft Editor/Assembler Plus from tape. That takes several minutes.
Load one segment of Weerd source code from a cassette tape.
- That will fail.
- Adjust the volume on the tape player.
- Try again.
- If it fails too many times, listen to the digital recording and try to find the second copy, saved right after the first one, and load that.
- Work for a while. Make changes.
- Rewind the cassette tape.
- Maybe switch tapes so as to have a backup.
- Write one copy of the source code.
- Write a second copy of the source code.