Tandy 200 BASIC tokenized file
Tandy 200 BASIC was a version of Microsoft BASIC for the Radio Shack Tandy 200 computer. The tokenizations for the TRS-80 Model 100 and Tandy 102 appear to be identical. The NEC PC-8201/8300 format is not the same, but should be similar.
Contents |
Tokens
Blank values indicate either that the token is unused or is used for something unknown.
| Hex | Dec | Token meaning | Notes |
|---|---|---|---|
| 80 | 128 | END | |
| 81 | 129 | FOR | |
| 82 | 130 | NEXT | |
| 83 | 131 | DATA | |
| 84 | 132 | INPUT | |
| 85 | 133 | DIM | |
| 86 | 134 | READ | |
| 87 | 135 | LET | |
| 88 | 136 | GOTO | |
| 89 | 137 | RUN | |
| 8A | 138 | IF | |
| 8B | 139 | RESTORE | |
| 8C | 140 | GOSUB | |
| 8D | 141 | RETURN | |
| 8E | 142 | REM | |
| 8F | 143 | STOP | |
| 90 | 144 | WIDTH | |
| 91 | 145 | ELSE | When tokenizing, the Tandy 200 always adds a colon (':') before the ELSE token (3A 91). If the user actually writes :ELSE it is tokenized as 3A 3A 91. |
| 92 | 146 | LINE | |
| 93 | 147 | EDIT | |
| 94 | 148 | ERROR | |
| 95 | 149 | RESUME | |
| 96 | 150 | OUT | |
| 97 | 151 | ON | |
| 98 | 152 | DSKO$ | |
| 99 | 153 | OPEN | |
| 9A | 154 | CLOSE | |
| 9B | 155 | LOAD | Note that LOADM is simply the token for LOAD followed by an ASCII 'M'. |
| 9C | 156 | MERGE | |
| 9D | 157 | FILES | |
| 9E | 158 | SAVE | |
| 9F | 159 | LFILES | |
| A0 | 160 | LPRINT | |
| A1 | 161 | DEF | |
| A2 | 162 | POKE | |
| A3 | 163 | ||
| A4 | 164 | CONT | |
| A5 | 165 | LIST | |
| A6 | 166 | LLIST | |
| A7 | 167 | CLEAR | |
| A8 | 168 | CLOAD | |
| A9 | 169 | CSAVE | |
| AA | 170 | TIME$ | |
| AB | 171 | DATE$ | |
| AC | 172 | DAY$ | |
| AD | 173 | COM | |
| AE | 174 | MDM | |
| AF | 175 | KEY | |
| B0 | 176 | CLS | |
| B1 | 177 | BEEP | |
| B2 | 178 | SOUND | |
| B3 | 179 | LCOPY | |
| B4 | 180 | PSET | |
| B5 | 181 | PRESET | |
| B6 | 182 | MOTOR | |
| B7 | 183 | MAX | |
| B8 | 184 | POWER | |
| B9 | 185 | CALL | |
| BA | 186 | MENU | |
| BB | 187 | IPL | |
| BC | 188 | NAME | |
| BD | 189 | KILL | |
| BE | 190 | SCREEN | |
| BF | 191 | NEW | |
| C0 | 192 | TAB( | |
| C1 | 193 | TO | |
| C2 | 194 | USING | |
| C3 | 195 | VARPTR | |
| C4 | 196 | ERL | |
| C5 | 197 | ERR | |
| C6 | 198 | STRING$ | |
| C7 | 199 | INSTR | |
| C8 | 200 | DSKI$ | |
| C9 | 201 | INKEY$ | |
| CA | 202 | CSRLIN | |
| CB | 203 | OFF | |
| CC | 204 | HIMEM | |
| CD | 205 | THEN | |
| CE | 206 | NOT | |
| CF | 207 | STEP | |
| D0 | 208 | + | |
| D1 | 209 | - | |
| D2 | 210 | * | |
| D3 | 211 | / | |
| D4 | 212 | ^ | |
| D5 | 213 | AND | |
| D6 | 214 | OR | |
| D7 | 215 | XOR | |
| D8 | 216 | EQV | |
| D9 | 217 | IMP | |
| DA | 218 | MOD | |
| DB | 219 | \ | |
| DC | 220 | > | |
| DD | 221 | = | |
| DE | 222 | ||
| DF | 223 | SGN | |
| E0 | 224 | INT | |
| E1 | 225 | ABS | |
| E2 | 226 | FRE | |
| E3 | 227 | INP | |
| E4 | 228 | LPOS | |
| E5 | 229 | POS | |
| E6 | 230 | SQR | |
| E7 | 231 | RND | |
| E8 | 232 | LOG | |
| E9 | 233 | EXP | |
| EA | 234 | COS | |
| EB | 235 | SIN | |
| EC | 236 | TAN | |
| ED | 237 | ATN | |
| EE | 238 | PEEK | |
| EF | 239 | EOF | |
| F0 | 240 | LOC | |
| F1 | 241 | LOF | |
| F2 | 242 | CINT | |
| F3 | 243 | CSNG | |
| F4 | 244 | CDBL | |
| F5 | 245 | FIX | |
| F6 | 246 | LEN | |
| F7 | 247 | STR$ | |
| F8 | 248 | VAL | |
| F9 | 249 | ASC | |
| FA | 250 | CHR$ | |
| FB | 251 | SPACE$ | |
| FC | 252 | LEFT$ | |
| FD | 253 | RIGHT$ | |
| FE | 254 | MID$ | |
| FF | 255 | ' (QUOTE) | When tokenizing, the single quote character expands to three characters: a colon (3A), the byte for REM (8E), and then FF. |
File Format
Tokenised BASIC code is a sequence of tokenized lines. Each tokenized line has the following format:
| Name | Length | Description |
|---|---|---|
| PL PH | 2 bytes | Address of the next line in memory, little endian. This data can be ignored as it is only a placeholder. The value of PL PH in a file is moot because the address is recalculated every time the program loads. Once in memory, PL PH is used to skip to the line required for GOTO, GOSUB, and READ, thus speeding up the program. |
| LL LH | 2 bytes | Line number, little endian. |
| B0 … BN | Any number | Sequence of tokens or ASCII characters. If a character's value is ≥ 128, then it is a token. All tokens are a single byte. |
| NULL | 1 byte | NULL byte (`0x00`) to signal end of line. |
Limits
- Line numbers can range from 0 to 65529 (but see variances below).
- Tokenized line length is limited to 256 characters, including the trailing NULL byte. (To do: double check this.)
Acceptable variances
While Tandy BASIC will never generate such files, it has no problem with a tokenized program that:
- Has line numbers out of order; they will be sorted when loaded.
- Contains duplicate line numbers; previous line is discarded.
- Contains arbitrary bytes for PL PH; they are always regenerated during loading.
- Has a ^Z (ASCII 26) at the end of the file.
- Contains illegal line numbers; this can be used to store hidden binary data according to John R. Hogerhuis.
Note that while these variances are accepted on an actual Model T device (Model 100, Tandy 200, or Tandy 102), emulators may not be able to handle such files. For example, the Virtual T emulator (as of version 1.7 in 2022) refuses to load tokenized BASIC programs that have lines out of order, duplicate lines, or bogus values for PL PH.
Details for PL PH
(Stub. This is where the correct calculation of PL PH values will go.)
