BBC Microcomputer User Guide
Acorn’s official end-user manual for the BBC Model A/B. Published 1982, shipped with every machine. Predates the Master Series.
Most of the manual is a BASIC tutorial (introducing variables, loops, procedures, etc.) — out of scope for a performance wiki. Several chapters are however the canonical primary source for things now buried in derived references:
- VDU control codes (Ch 34) — the bible for what each VDU n does. The wiki’s
os/vdu.mdis sourced primarily from here. - Advanced graphics + PLOT codes (Ch 29) — original list of PLOT codes 0-95 (later extended on Master).
- FX/OSBYTE calls (Ch 42) — first published OSBYTE reference (incomplete; superseded by NAUG App A/B).
- Error messages (Ch 46) — canonical Model B error number ↔ message map.
- Appendix (Ch 48) — ASCII codes, INKEY numbers, character codes table, machine ID table.
For Master-era content, prefer master-arm. For Master-era OSBYTE/OSWORD, prefer naug-appendix-ab. The User Guide is the authority for the original VDU driver spec — the Model B’s behaviour defined what every later machine had to remain compatible with.
Bibliographic
- Title: BBC Microcomputer System User Guide
- Author: John Coll (with Acorn editorial input)
- Publisher: Acorn Computers Ltd. / British Broadcasting Corporation
- Year: 1982 (first ed.); reprinted with minor updates through 1984.
- PDF source: bitshifters/bbc-documents archive
- Format: 522-page PDF.
Chapter index (performance/hardware-relevant only)
| Ch | Title | Pages | Filed into |
|---|---|---|---|
| 1-27 | BASIC tutorial chapters | 9-126 | out of scope (BASIC programming primer) |
| 28 | Teletext and MODE 7 | 152-161 | Cross-checked against saa5050 — UG is beginner-level intro; technical detail already in saa5050.md (Mullard datasheet + BeebWiki sources). bbc-user-guide added to saa5050 sources. |
| 29 | Advanced Graphics | 162-181 | Created plot-codes (PLOT k=0-95 from this chapter + k=96-255 from Master ARM Ch 6) |
| 30 | Sound | 182-189 | cross-checked vs sn76489 / sound — no new content |
| 31-33 | File handling, BASIC keywords | 190-378 | out of scope |
| 34 | VDU drivers | 379-391 | Created vdu (full VDU 0-31 + 127 control code reference) |
| 35-41 | Cassette / printers / misc | 392-417 | out of scope or already in NAUG |
| 42 | FX Calls and OSBYTE calls | 420-443 | Cross-checked against osbyte — User Guide’s original OSBYTE list is a strict subset of NAUG App A/B and Master ARM additions. bbc-user-guide added to osbyte sources. |
| 43 | Assembly language | 444-468 | out of scope — already covered by NAUG Ch2 ingest |
| 44 | Analogue input | 469-472 | cross-checked vs upd7002-adc — no new content |
| 45 | Expanding the system | 473-475 | pending — original 1MHz / Tube / disc expansion overview |
| 46 | Error messages | 476-484 | Created errors (BASIC 0-44 + CFS 216-223 + MOS 250+ + filing-system error tables) |
| 48 | Appendix | 487-514 | Cross-checked: ASCII / INKEY tables already covered in keyboard (via NAUG Ch14 + Master ARM Ch 5 ingest); BASIC keyword token table covered in basic-assembler. bbc-user-guide added to keyboard.md sources. |
Filed into
- Ch 34 (VDU drivers) → created vdu (full VDU control code reference table, per-code semantics, byte-count for each).
- Ch 29 (Advanced Graphics) + Ch 33 (PLOT BASIC keyword) → created plot-codes covering PLOT k=0-95 (line variants, fills, triangles, single points) from User Guide and k=96-255 (rectangle, parallelogram, circle, ellipse, flood fill) from Master ARM Ch 6.
- Ch 46 (Error messages) → created errors (BASIC 0-44 alphabetical, CFS 216-223, MOS 250+, DFS/ADFS/NFS conventions, BRK-raising-from-user-code pattern).
This wiki is curated by Claude following the LLM-Wiki methodology — a human curates source documents, the LLM compiles structured cross-linked markdown. Content may contain errors, omissions, or stale claims. For authoritative information refer to the original source documents in the bbc-documents GitHub archive.