Notes For V3.4-0

The memory layout for the Interdata simulators has been changed.
Do not use Interdata SAVE files from prior revisions with V3.4.

1. New Features in 3.4

1.1 SCP and Libraries

- Revised interpretation of fprint_sym, fparse_sym returns
- Revised syntax for SET DEBUG
- DO command nesting allowed to ten levels

1.2 Interdata

- Revised memory model to be 16b instead of 8b

1.3 HP2100

- Added Fast FORTRAN Processor instructions
- Added SET OFFLINE/ONLINE and SET UNLOAD/LOAD commands to tapes and disks

2. Bugs Fixed in 3.4-0

2.1 Interdata

- Fixed bug in show history routine (from Mark Hittinger)
- Fixed bug in initial memory allocation

2.2 PDP-10

- Fixed TU bug, ERASE and WREOF should not clear done (reported by
  Rich Alderson)
- Fixed TU error reporting

2.3 PDP-11

- Fixed TU error reporting

PDP8/pdp8_mt.c

@@ -1,6 +1,6 @@
 /* pdp8_mt.c: PDP-8 magnetic tape simulator
 
-   Copyright (c) 1993-2004, Robert M Supnik
+   Copyright (c) 1993-2005, Robert M Supnik
 
    Permission is hereby granted, free of charge, to any person obtaining a
    copy of this software and associated documentation files (the "Software"),
@@ -25,6 +25,7 @@
 
    mt		TM8E/TU10 magtape
 
+   18-Mar-05	RMS	Added attached test to detach routine
    25-Apr-03	RMS	Revised for extended file support
    29-Mar-03	RMS	Added multiformat support
    04-Mar-03	RMS	Fixed bug in SKTR
@@ -563,6 +564,7 @@ t_stat mt_detach (UNIT* uptr)
 {
 int32 u = uptr - mt_dev.units;				/* get unit number */
 
+if (!(uptr->flags & UNIT_ATT)) return SCPE_OK;		/* check for attached */
 if (!sim_is_active (uptr)) uptr->USTAT = STA_REM;
 if (u == GET_UNIT (mt_cu)) mt_updcsta (uptr);
 return sim_tape_detach (uptr);