Editing TRS-80 Model 100 (section)

== Data storage ==
The computer included a port to connect a cassette audiotape recorder for storage of data and programs. Programs written in BASIC could load and save data and programs to the cassette device. Control was provided to start and stop the tape, but the operator would have to manually put the cassette recorder into "record" or "play" mode as needed. 

A popular alternative is the ''Tandy Portable Disk Drive'' (TPDD),<ref>{{cite web|title=Radio Shack Computer Catalog RSC-15, page 50|url=http://www.radioshackcatalogs.com/html/catalogs_extra/1986_rsc-15/h050.html|website=Radio Shack Catalogs dot com|publisher=Tandy/Radio Shack|access-date=April 11, 2017|archive-date=October 3, 2014|archive-url=https://web.archive.org/web/20141003160646/http://www.radioshackcatalogs.com/html/catalogs_extra/1986_rsc-15/h050.html|url-status=live}}</ref> introduced in late 1985, an RS-232 serial device capable of storing 100&nbsp;KB of data [[Frequency modulation encoding|FM-encoded]] on a 3.5-inch single-sided double-density diskette;<ref>[http://www.classiccmp.org/cini/pdf/Tandy/Portable%20Disk%20Drive%20Operation%20Manual.pdf Portable Disk Drive Operation Manual] {{Webarchive|url=https://web.archive.org/web/20170824225424/http://www.classiccmp.org/cini/pdf/Tandy/Portable%20Disk%20Drive%20Operation%20Manual.pdf |date=August 24, 2017 }}, Cat. No. 26-3808, 1985, TANDY<!-- https://web.archive.org/web/20170615150507/http://www.classiccmp.org/cini/pdf/Tandy/Portable%20Disk%20Drive%20Operation%20Manual.pdf --></ref><ref>[http://www.classiccmp.org/cini/pdf/Tandy/Portable%20Disk%20Drive%20Command%20Reference.pdf Tandy Portable Disk Drive (PDD1 and PDD2)Command Reference] {{Webarchive|url=https://web.archive.org/web/20170824225424/http://www.classiccmp.org/cini/pdf/Tandy/Portable%20Disk%20Drive%20Command%20Reference.pdf |date=August 24, 2017 }}<!-- https://web.archive.org/web/20170615150507/http://www.classiccmp.org/cini/pdf/Tandy/Portable%20Disk%20Drive%20Operation%20Manual.pdf --></ref> this drive is identical to the Brother FB100 drive for [[knitting machine]]s.<ref>[http://www.k2g2.org/wiki:brother_fb-100 brother fb-100] {{Webarchive|url=https://web.archive.org/web/20170615150921/http://www.k2g2.org/wiki:brother_fb-100 |date=June 15, 2017 }} wiki<!-- https://web.archive.org/web/20170615150921/http://www.k2g2.org/wiki:brother_fb-100 --></ref><ref>[http://machineknittingetc.com/brother-fb100-floppy-drive-user-guide.html Brother FB100 Floppy Drive User Guide] {{Webarchive|url=https://web.archive.org/web/20170706172335/http://machineknittingetc.com/brother-fb100-floppy-drive-user-guide.html |date=July 6, 2017 }}, Machine Knitting etc<!-- https://web.archive.org/web/20160620045820/http://machineknittingetc.com:80/brother-fb100-floppy-drive-user-guide.html --></ref> A second version, the ''TPDD2'',<ref>{{cite web|title=Radio Shack Computer Catalog RSC-17B, page 42|url=http://www.radioshackcatalogs.com/html/catalogs_extra/1987_rsc-17b/h042.html|website=Radio Shack Catalogs dot com|publisher=Tandy/Radio Shack|access-date=April 11, 2017|archive-date=October 3, 2014|archive-url=https://web.archive.org/web/20141003162209/http://www.radioshackcatalogs.com/html/catalogs_extra/1987_rsc-17b/h042.html|url-status=live}}</ref> can store up to 200&nbsp;KB.

A Disk/Video Interface expansion box was released in 1984, with one single-sided double-density 180 KB 5-1/4 inch disk drive and a [[Cathode-ray tube|CRT]] video adapter. This allows the Model 100 to display 40 or 80 column video on an external television set or video monitor. One empty drive bay permits the installation of a second disk drive.<ref>{{cite web|title=Radio Shack Computer Catalog RSC-12, page 59|url=http://www.radioshackcatalogs.com/html/catalogs_extra/1985_rsc-12/h059.html|website=Radio Shack Catalogs dot com|publisher=Tandy/Radio Shack|access-date=April 10, 2017|archive-date=November 7, 2013|archive-url=https://web.archive.org/web/20131107201421/http://www.radioshackcatalogs.com/html/catalogs_extra/1985_rsc-12/h059.html|url-status=live}}</ref>

Another popular form of data backup was that of file transfer to a desktop computer, via either the modem connected to a telephone line, or the RS-232 serial port connected to a [[null modem]] cable. The built-in TELCOM firmware makes this a convenient option. The [[TRS-80 Model 4]]'s TRSDOS 6 operating system includes a utility called TAPE100 that uses the Model 4's cassette port to read and write tapes created by a Model 100, the data of which are stored in TRSDOS disk files. Also because TRSDOS 6 included a communications application (COMM/CMD), the Model 100 proved a popular "peripheral" for the Model 4 customer.

A bar code reader wand was also offered.