The Linux Serial HOWTO The Linux Serial HOWTO revised by David S.Lawyer [e-mail] original by Greg Hankins v1.12, July 1998This document describes serial port features not covered by Text-Terminal-HOWTO or Serial-Programming-HOWTO. It covers mostly getty, multiport serial cards and modems.1. Introduction1.1 Copyright1.2 Related HOWTO's re: the Serial Port1.3 Release Notes1.4 New Versions Of This Document1.5 Feedback1.6 Disclaimer2. Supported Serial Hardware2.1 Standard PC Serial Boards2.2 Plug And Play (PnP) Modems2.3 Dumb Multiport Serial Boards (with 8250/16450/16550A UART's)2.4 Intelligent Multiport Serial Boards2.5 Unsupported Serial Hardware3. What Are The Names Of The Serial Ports?3.1 Devices: modem, mouse3.2 The cua Device3.3 Serial Port Devices and Numbers In /dev3.4 Notes For Dumb Multiport Boards3.5 Notes For Intelligent Multiport Boards4. Interesting Programs You Should Know About4.1 What is getty?4.2 What is setserial?5. How Do I Dial Out With My Modem?5.1 Hardware Requirements5.2 Talking To Your Modem5.3 Dial Out Modem Configuration5.4 Hardware Flow Control6. How Do I Dial In And Out With My Modem Using getty_ps6.1 Dial In And Out Modem Configuration6.2 Installing getty_ps7. uugetty7.1 Setting up uugetty7.2 Customizing uugetty8. How Do I Set Up A Terminal Connected To My PC?8.1 Hardware Requirements8.2 Setting up getty (part of getty_ps)8.3 Notes On Setting Up A PC As A Terminal9. Can I Use More Than Two Serial Devices?9.1 Choosing Serial Device Interrupts9.2 Setting Serial Device Addresses10. How Do I Set Up My Serial Ports For Higher Speeds? What Speed Should I Use With My Modem?11. Communications Programs And Utilities12. Serial Tips And Miscellany12.1 kermit and zmodem12.2 Setting Terminal Types Automagically12.3 Color ls On Serial Connections12.4 Printing To A Printer Connected To A Terminal12.5 Can Linux Configure The Serial Devices Automagically?12.6 Using A Serial Console12.7 Higher Serial Throughput13. One Step Further...13.1 What Are Lock Files?13.2 ``baud'' Vs. ``bps''13.3 What Are UARTs? How Do They Affect Performance?14. Troubleshooting14.1 I Keep Getting ``line NNN of inittab invalid''14.2 When I Try To Dial Out, It Says ``/dev/cuaN: Device or resource busy''14.3 I Keep Getting ``Getty respawning too fast: disabled for 5 minutes''14.4 Serial Devices Are Slow, Or Serial Devices Can Only Send In One Direction14.5 My Modem Is Hosed After Someone Hangs Up, Or uugetty doesn't respawn14.6 I Have My Terminal Connected To My PC, But After I Type In A Login Name, It Just Locks Up14.7 At High Speeds, My Modem Looses Data14.8 On Startup, Linux Doesn't Report The Serial Devices The Way I Have Them Configured14.9 rz And/Or sz Don't Work When I Call My Linux Box On A Modem14.10 My Screen Is Displaying Funny Looking Characters14.11 getty Or uugetty Still Doesn't Work15. Other Sources Of Information16. Contributions i