| 0300 | 2 | X/Right coordinate of graphics window |
| 0302 | 2 | Y/Bottom coordinate of graphics window |
| 0304 | 2 | X/left coordinate of graphics window |
| 0306 | 2 | Y/Top coordinate of graphics window |
| 0308 | 1 | X/left of text window |
| 0309 | 1 | Y/bottom of text window |
| 030A | 1 | X/right of text window |
| 030B | 1 | Y/top of text window |
| 030C | 2 | X coordinate of graphics origin |
| 030E | 2 | Y coordinate of graphics origin |
| 0310 | 4 | Current graphics origin in external coordinates |
| 0314 | 4 | Current graphics cursor in external coordinates |
| 0318 | 1 | Text cursor X coordinate |
| 0319 | 1 | Text cursor Y coordinate |
| 031A | 1 | Line within current graphics char of graphics point |
| 031B | 4 | Graphic workspace or start of VDU queue |
| 031F | 5 | VDU queue |
| 0324 | 4 | Current graphics cursor in internal coordinates |
| 033C | 2 | Graphics cursor Y coordinate |
| 033E | 2 | Graphics cursor X coordinate |
| 034A | 2 | Text cursor address |
| 034C | 2 | Text window width in bytes |
| 034E | 1 | High byte of screen memory start address, Low is 0x00 |
| 034F | 1 | Bytes per character |
| 0350 | 2 | Address of top-left of screen |
| 0352 | 2 | No bytes per line |
| 0354 | 1 | Screen memory length |
| 0355 | 1 | Mode |
| 0356 | 1 | Screen memory map type |
| 0357 | 1 | Foreground text colour |
| 0358 | 1 | Background text colour |
| 0359 | 1 | Graphics foreground mask |
| 035A | 1 | Graphics background mask |
| 035B | 1 | Graphics foreground modifier |
| 035C | 1 | Graphics background modifier |
| 035D | 2 | General VDU jump vector |
| 035F | 1 | Record of last setting of 6845 cursor start reg |
| 0360 | 1 | No colours available |
| 0361 | 1 | No of pixels per byte |
| 0362 | 2 | left/right colour masks |
| 0364 | 2 | Text input cursor coordinates |
| 0366 | 1 | Teletext output cursor character |
| 0367 | 1 | Font flag (RAM or ROM)
| Bit 1 |
Characters 224-255 |
| Bit 2 |
Characters 192-223 |
| Bit 3 |
Characters 160-191 |
| Bit 4 |
Characters 128-159 |
| Bit 5 |
Characters 96-127 |
| Bit 6 |
Characters 64-95 |
| Bit 7 |
Characters 32-63 |
|
| 0368 | 7 | Font location bytes |
| 036F | 16 | Palette mapping actual colour for each logical colour |
| 0380 | 29 | Header block for BPUT file store |
| 039D | 1 | Offset of next byte to be output into BPUT buffer |
| 039E | 1 | Offset of next byte to be read from BGET buffer |
| 039F | 8 | Unused |
| 03A7 | 11 | Filename of file being BGETed |
| 03B2 | 31 | Block header of most recent block read |
| 03B2 | 12 | Filename terminated by zero |
| 03BE | 4 | Load address |
| 03C2 | 4 | Exec address |
| 03C6 | 2 | Block number address |
| 03C8 | 2 | Block length |
| 03CA | 1 | Block flag byte |
| 03CB | 4 | 4 spare bytes |
| 03CF | 2 | Checksum |
| 03D1 | 1 | Sequential block gap, *OPT3 |
| 03D2 | 11 | Filename of file being searched for |
| 03DD | 2 | Number of next block expected for BGET |
| 03DF | 1 | Copy of block flag of last block read |
| 03E0 | 32 | Runtime keyboard buffer |