CP/M
Many of these needed BYE and KMD to handle modem interactions and file transfers
- RBBS written in Microsoft Basic – really slow login with more than a few users
- PBBS 4 written in Z80 Assembly Code by Russ Pencin
- QBBS (QuickBBS)
- TBBS
- XBBS
- MikroKom
- Bulldog BBS written in BDS C
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