From the Club 100 support files (www.club100.org)...

TPDD / TPDD2 DIFFERENCES

    Drive RSNum   Media        Dirs Files/Dir TotalBytes  StockDOS
    TPDD  26-3808 dssd or dsdd    1        40  Aprox100K  floppy.co
    TPDD2 26-3814 dssd or dsdd    2        40  Aprox200K  floppy

1) The tpdd2 will read tpdd2 and tpdd disks but write only tpdd2 disks.  The 
tpdd will only read/write it's own disks. 

2) Tandy used to repair these drives but no longer... so don't ask! Acquire 
multiple units as backups. 

3) Neither drives disks may be read by any MS-DOS or Apple computers. Many 
excellent engineers have tried and failed.  There is software available to 
allow a Cambridge Z88 to access a tpdd2. 

4) The WP-2 has a built in DOS to access the tpdd2.  WP2DOS Plus (MS-DOS 
program) is software available for a WP-2 to use a MS-DOS computer as if it 
were a tpdd2.  And although it was designed to work in DOS, fellow WP-2 users 
report that is works in Windows 95, 98 and NT. 

5) Best direct tpdd/tpdd2 MS-DOS access: Lapdos II (won't run under Windows or 
on Pentiums but works great on slow 486s, 386s, XTs, and PCs).  Lapdos II will 
also access Model 100, 102, 200 and NEC PC8201a (AKA Model "T" computers) 
directly via null-modem cable. 

6) DeskLink (MS-DOS program) allows direct access from a Model 100, 102, 200 
or NEC PC8201a to a MS-DOS computer as if the DOS computer were a tpdd.  
DeskLink will run on Pentiums but not from within Windows or OS/2.  It will 
run from within Desqview.  Free from Club 100: See Club 100 Library, Member 
Uploads category, DL-ARC.EXE file (make subdirectory named ROOT and run the 
DL-ARC.EXE program in that subdirectory) it's self deARCing. Original docs 
were scanned and OCRed and included in Word 6.0 .doc files and in ASCII .txt 
files in the archive. 

8) There are tpdd and tpdd2 programs in the Library, Drives category. 

9) There is tpdd and tpdd2 information in the Library, Technical Reference 
category. 

10) Best dos to use: TS-DOS on ROM or RAM.  Will access both tpdd and tpdd2 
drives.  RAM version directly loadable via boot instructions or via loaders in 
option ROMs: Ultimate ROM II, Sardine, and accessible via instruction in the 
ROM2/Cleuseau Model 100/102 developers version. 

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