| 0200 | 2 | USERV | User Vector |
| 0202 | 2 | BRKV | BRK Vector |
| 0204 | 2 | IRQ1V | Interrupt request Vector 1 |
| 0206 | 2 | IRQ2V | Interrupt request Vector 2 |
| 0208 | 2 | CLIV | OSCLI Vector |
| 020A | 2 | BYTEV | OSBYTE Vector |
| 020C | 2 | WORDV | OSWORD Vector |
| 020E | 2 | WRCHV | OSWRCH Vector |
| 0210 | 2 | RDCHV | OSRDCH Vector |
| 0212 | 2 | FILEV | OSFILE Vector |
| 0214 | 2 | ARGSV | OSARGS Vector |
| 0216 | 2 | BGETV | OSBGET Vector |
| 0218 | 2 | BPUTV | OSBPUT Vector |
| 021A | 2 | GBPBV | OSGBPB Vector |
| 021C | 2 | FINDV | OSFIND Vector |
| 021E | 2 | FSCV | File system control entry vector |
| 0220 | 2 | EVNTV | Event interrupt vector |
| 0222 | 2 | UPTV | User print routine vector |
| 0224 | 2 | NETV | Used by ECONET to take control of computer |
| 0226 | 2 | VDUV | Unrecognised VDU23 & PLOT commands |
| 0228 | 2 | KEYV | Full keyboard access |
| 022A | 2 | INSV | Insert into buffer vector |
| 022C | 2 | REMV | Remove from buffer vector |
| 022E | 2 | CNPV | Count/purge buffer vector |
| 0230 | 2 | IND1V | Spare Vector |
| 0232 | 2 | IND2V | Spare Vector |
| 0234 | 2 | IND3V | Spare Vector |
| 0236 | 2 | | Start address of OS variables |
| 0238 | 2 | | Address of ROM pointer table |
| 023A | 2 | | Address of ROM information table |
| 023C | 2 | | Address of key translation table |
| 023E | 2 | | Start address of VDU variables |
| 0240 | 1 | | CFS timeout counter |
| 0241 | 1 | | Input source |
| 0242 | 1 | | Keyboard semaphore |
| 0243 | 1 | | Primary OSHWM |
| 0244 | 1 | | Current OSHWM |
| 0245 | 1 | | RS423 mode |
| 0246 | 1 | | Character definition explosion state |
| 0247 | 1 | | Cassette/ROM filing system switch |
| 0248 | 1 | | RAM copy of ULA control reg |
| 0249 | 1 | | RAM copy of ULA palette reg |
| 024A | 1 | | ROM number active at last BRK |
| 024B | 1 | | ROM number containing BASIC |
| 024C | 1 | | Current ADC channel |
| 024D | 1 | | Max ADC channel |
| 024E | 1 | | ADC conversion type |
| 024F | 1 | | RS423 user flag |
| 0250 | 1 | | RS423 control flag |
| 0251 | 1 | | Flashing colours counter |
| 0252 | 1 | | Mark period counter |
| 0253 | 1 | | Space period counter |
| 0254 | 1 | | Keyboard auto-repeat delay |
| 0255 | 1 | | Keyboard auto-repeat period |
| 0256 | 1 | | *EXEC file handle |
| 0257 | 1 | | *SPOOL file handle |
| 0258 | 1 | | ESCAPE/BREAK effect |
| 0259 | 1 | | ECONET keyboard disable |
| 025A | 1 | | Keyboard status |
| 025B | 1 | | RS423 handshake extent |
| 025C | 1 | | RS423 input supression flag |
| 025D | 1 | | RS423/cassette selection flag |
| 025E | 1 | | Econet OS call interception status |
| 025F | 1 | | Econet OSRDCH interception status |
| 0260 | 1 | | Econet OSWRCH interception status |
| 0261 | 1 | | Speech suppression status |
| 0262 | 1 | | Sount suppression status |
| 0263 | 1 | | BELL channel |
| 0264 | 1 | | BELL envelope number/volume |
| 0265 | 1 | | BELL frequency |
| 0266 | 1 | | BELL duration |
| 0267 | 1 | | Startup message & !BOOT options |
| 0268 | 1 | | Length of soft key string |
| 0269 | 1 | | No of lines printed since last page |
| 026A | 1 | | No of items in VDU queue |
| 026B | 1 | | TAB character value |
| 026C | 1 | | ESCAPE character value |
| 026D | 1 | | Character 0xC0 to 0xCF status |
| 026E | 1 | | Character 0xD0 to 0xDF status |
| 026F | 1 | | Character 0xE0 to 0xEF status |
| 0270 | 1 | | Character 0xF0 to 0xFF status |
| 0271 | 1 | | Function key status |
| 0272 | 1 | | SHIFT+Function key status |
| 0273 | 1 | | CTRL+Function key status |
| 0274 | 1 | | CTRL+SHIFT+Function key status |
| 0275 | 1 | | ESCAPE key status |
| 0276 | 1 | | ESCAPE key effect |
| 0277 | 1 | | IRQ bit mask for user 6522 |
| 0278 | 1 | | IRQ bit mask for 6850 |
| 0279 | 1 | | IRQ bit mask for system 6522 |
| 027A | 1 | | Tube presence flag |
| 027B | 1 | | Speech processor presence flag |
| 027C | 1 | | Write character destination status |
| 027D | 1 | | Cursor editing status |
| 027E | 3 | | Unused |
| 0281 | 1 | | Used by *FX1 |
| 0282 | 1 | | RAM copy of serial processor ULA |
| 0283 | 1 | | Timer switch state |
| 0284 | 1 | | Soft key consistancy flag |
| 0285 | 1 | | Printer destination flag |
| 0286 | 1 | | Character ignored by printer |
| 0287 | 3 | | BREAK intercept code |
| 028A | 2 | | Unused |
| 028C | 1 | | Current language ROM number |
| 028D | 1 | | Last BREAK type |
| 028E | 1 | | Available RAM |
| 028F | 1 | | Start up option flag |
| 0290 | 1 | | VDU vertical adjust, set by *TV |
| 0291 | 1 | | Interlace toggle flag, set by *TV |
| 0292 | 5 | | First copy of system clock values |
| 0297 | 5 | | Second copy of system clock values |
| 029C | 5 | | Countdown interval timer value |
| 02A1 | 16 | | Paged ROM type table |
| 02B1 | 2 | | INKEY countdown timer |
| 02B3 | 3 | | OSWORD 0x01 workspace |
| 02B6 | 4 | | Low bytes of most recent analogue converter values |
| 02BA | 4 | | High bytes of most recent analogue converter values |
| 02BE | 1 | | Analogue system flag |
| 02BF | 10 | | Event enable flags |
| 02C9 | 1 | | Soft key expansion pointer |
| 02CA | 1 | | First auto repeat count |
| 02CB | 3 | | Two key rollover processing workspace |
| 02CE | 1 | | Sound semaphore |
| 02CF | 9 | | Buffer busy flags |
| 02D8 | 9 | | Buffer start indices |
| 02E1 | 9 | | Buffer end indices |
| 02EA | 2 | | Block size of current resident block of open cassette input file |
| 02EC | 1 | | Block flag of current resident block of open cassette input file |
| 02ED | 1 | | Last character in currently resident block of open cassette input file |
| 02EE | 18 | | Used as area to build OSFILE control blocks for *LOAD & *SAVE |