website/content/museum/tandy-radio-shack-trs-80-model-4p.md

title, categories, types, origins, years, cpus, params

title	categories	types	origins	years	cpus	params
Tandy Radio Shack TRS 80 Model 4P	Computers	Portable	U.S.A.	1983	Z80A	name image company company_name specs tabs photos hardware emulators links comments related oc_id source TRS 80 Model 4P /media/museum/photos/tandy_model4p_system_2.jpg /companies/tandy-radio-shack Tandy Radio Shack label value NAME TRS 80 Model 4P label value MANUFACTURER Tandy Radio Shack label value TYPE Portable label value ORIGIN U.S.A. label value YEAR October 1983 label value BUILT IN LANGUAGE None label value KEYBOARD Typewriter style, 70 keys with numeric keypad and arrow keys label value CPU Z80A label value SPEED 4 MHz label value RAM 64 or 128 KB label value ROM 4 KB label value TEXT MODES 32 or 64 x 16 / 64 x 40 / 80 x 24 label value GRAPHIC MODES None label value COLORS Monochrome label value SOUND Buzzer label value I/O PORTS Parallel, Serial, Expansion bus label value BUILT IN MEDIA 2 x 5.25'' SS SD 180 KB floppy drives\ Very late models had double-sided TEAC drives label value OS TRS-DOS 6.0 to 6.2, LS-DOS 6.3, CP/M label value POWER SUPPLY Built-in power supply unit label value PERIPHERALS Built-in 300-baud modem, external HDD label value PRICE $1,790 photos hardware emulators links title subtitle text image MODEL 4P /media/museum/photos/tandy_model4p_front_ebay_2.jpg title subtitle text image FRONT /media/museum/photos/tandy_model4p_front_ebay_1.jpg title subtitle text image KEYBOARD /media/museum/photos/tandy_model4p_keyboard_1.jpg title subtitle text image BACK from left to right: - RS232C connector\ - I/O bus\ - parallel port /media/museum/photos/tandy_model4p_back_1.jpg title subtitle text image CLOSED /media/museum/photos/tandy_model4p_closed_1.jpg title subtitle text image REMOTE UNIT ACTIVE Serial# 26-1210 This rare unit is meant for teachers to control up to 16 TRS-80 Model 1 from a another TRS-80 equiped with min-disk. All the controled TRS-80 model 1 must be equiped with Level II. It cost 2895fr (France, 1981) /media/museum/hardware/tandy_trs80-m1_remote-unit-active.jpg title subtitle text image NETWORK II BOX p/n 26-1211 This box allowed up to 16 TRS computer to be networked. Three network boxes were released by Tandy (I, II and III).\ The Network II required verbal communication between the server operator and the remote user, and data transfer had to be completed one user at a time.\ The network III allowed automated control of the network so that users could easily access programs and data stored on the server's storage device. Thanks to **David Sutherland** for the pictures. /media/museum/hardware/tandy_network2_s1.jpg title subtitle text image DMP-200 80-column, 100 cps dot matrix printer. /media/museum/hardware/tandy_model3_dmp200_s1.jpg title subtitle text image DAISY WHEEL PRINTER II Serial# 26-1158 This is a high-quality printer meant to be used with wordprocessors. Some interchangeable daisy-wheels were available (Courrier, Elite, Madeleine). It could print 163 characters per line (34cm), at a 43 cps rate. It cost 9595fr (France, 1981) /media/museum/hardware/tandy_trs80-m1_daisy-wheel-printer-2_1.jpg title subtitle text image LINE PRINTER I Ref# 26-7017 This printer was a custom version of the Oki Microline 80.\ Printed lower and upper case on paper rolls or listing paper (24cm wide) from 40 to 80 columns/line, at a speed rate of 28 lines/minute. It cost 716 Euros in 1981 (France). /media/museum/hardware/tandy_model1_lineprinter1_s1.jpg title subtitle text image LINE PRINTER III Serial# 26-1156 This printer can print lower and upper case, at a speed rate of 120 c/s, on paper up to 38cm wide. It is conceived for intensive use ! It cost 9950fr in 1981 (France). /media/museum/hardware/tandy_trs80-m1_line-printer-3_1.jpg title subtitle text image LINE PRINTER VI Serial# 26-1166 This large printer can print lower and upper case, graphic characters and symbols at a speed rate of 100 c/s ! This is definately a professional printer. It cost 5495fr in 1981 (France). /media/museum/hardware/tandy_trs80-m1_line-printer-6_1.jpg title subtitle text image TP-10 THERMAL PRINTER Box /media/museum/hardware/tandy_trs80_tp-10_thermal-printer_box.jpg title subtitle text image EXATRON Stringy Floppy drive The Exatron Stringy Floppy (ESF) was a low-cost data—storage system that fitted the gap, between cassettes and disk drives.\ The system was based on a miniature endless—loop tape cartridge called a "wafer".\ The amount of data that could be recorded on a wafer depended on the length of tape in it, typically, a 50—foot wafer could hold at least 40 KB of programs or data. **Matt** reports to us:\ A curiousity about the model 1, CPU SPEED had a direct relatonship with STORAGE CAPACITY. if you doubled the clock speed of your MODEL 1 CPU you doubled the amount of data you could store on your stringy floppies. this is a feat that no other computer no matter how many ghz you have in your PC can do today without using compression. Thanks to **David Sutherland** for the pictures /media/museum/hardware/tandy_model3_exatronwafer_s1.jpg title url platform text David Keil's TRS-80 Model III/4/4P Emulator Page http://discover-net.net/~dmkeil/trs80/model4.htm MS DOS This program emulates a complete TRS-80 title url platform text Matthew Reed's TRS-80 Emulator Web Site http://www.arrowweb.com/mkr/ MS DOS This page offers shareware versions of a TRS-80 Model 4 emulator and a TRS-80 Model 1-2 emulator title url platform text TRS-80 Model III/4 Emulator http://www.vavasour.ca/jeff/trs80.html#model4 MS DOS This TRS-80 Model III/4 Emulator is a commercial product title url platform text xtrs: TRS-80 Model I/III/4 Emulator for Unix http://www.tim-mann.org/xtrs.html Unix / Linux xtrs is a Radio Shack TRS-80 Model I/III/4/4P emulator for Unix and the X Window System title url platform text TRS-80 Level I BASIC in a browser http://www.vavasour.ca/jeff/trs80.html#simulator Other platform With this Java emulator, you'll be able to write a BASIC program directly in your browser! title url platform text Ira Goldklang's TRS-80 Revived Pages http://www.trs-80.com/trs80-e.htm Multiplatform A complete list of TRS-80 emulators for various platforms ! title url platform text MESS http://www.mess.org Multiplatform MESS emulator also emulates a TRS-80 systems title url text 8bit-micro.com - Online TRS-80 Computer Magazine HTTP://WWW.8BIT-MICRO.COM Online Magazine dedicated to the TRS-80 and other Vintage - Monthly Issues title url text David's TRS-80 Page http://freespace.virgin.net/david.sampson/ title url text Ira Goldklang's TRS-80 Revived Pages http://www.trs-80.com/ Lof of infos about all TRS-80 computers title url text Java TRS-80 Model 1 BASIC Interpreter http://ganley.org/software/trs80.html title url text Mike's Personal Computer Museum http://personal.nbnet.nb.ca/mclays/trsmod1.html Level 1 & 2 Basic summaries, Tandy time-lines, price-list, etc ... ! title url text RadioShackCatalogs.com http://www.RadioShackCatalogs.com Here, you can actually/virtually flip-through the pages to view the content of every RadioShack catalog! title url text The TRS-80 Home Page http://www.kjsl.com/trs80 Full of infos title url text Tim Mann's TRS-80 Page http://www.tim-mann.org/trs80.html Infos, tools and home of xtrs, a Model I/III/4 emulator for Unix title url text Web Wiz CAPTCHA http://www.webwizcaptcha.com Discussion about Tandy computers author date text Steve mills (Corvallis or) Monday 4th June 2018 Trs80 model 4p for sale author date text CJ (Virginia) Sunday 1st April 2018 I own a 4P myself, and thought I would add some more specific technical details - The 180K disk drives it uses are Tandon brand drives, model TM50-1, belt-driven.\ The Z80A CPU is SGS Thompson branded, model Z8400AB1. author date text Jeff Gillis (united states) Monday 17th July 2017 Unbelievably, I actually have the original cardboard box for a TRS 80 model 4P that I recovered from my folks attic where it sat undisturbed for decades. The internal packing material is long gone, but the box itself is in very good shape. I was going to flatten it and recycle it unless someone wants it. Any takers? author date text Marcus N. (Germany) Monday 12th December 2016 Dear Mr. Bryant, do you still have these manuals and Softwaredisks? I''m about to buy a TRS-80 4p with nothing except the defective machine... I would be so happy if you could send it over here to Germany by Mail postage - of course all on my cost :-) author date text Dean Notarnicola (NJ, USA) Tuesday 10th November 2015 Harry and John: Do you still have those Model 4P computers? author date text Harry Bryant (United States) Saturday 29th August 2015 I have a TRS80 4P and assoiated manuals and software. I''d gladly donate it to a hobbiest/museum for the cost of shipment. author date text Chuck Rose Thursday 15th January 2015 My model 4P had double sided drives just like the 4D. I developed with it mostly in CP/M mode because it had the bigger market compared to the model 4. author date text John E Iacono (USA) Monday 13rd October 2014 I have a 4P that has not been turned on for about 20 years. Also several hundred dsdd floppies, if anyone is interested. We used it in our accounting company for several years. author date text Richard Thursday 10th November 2011 I have this computer but do not have a power cord. Would any power cord work? author date text Richard Thursday 10th November 2011 I have this computer but do not have a power cord. Would any power cord work? author date text James (USA) Saturday 4th June 2011 I am still in possession of the Model 4P that my father purchased for me in 1984. (my junior year of HS.) The unit is still in functional condition, although the floppy''s are getting worn out. Anyone know where I could find replacement disks for it ?? author date text Charles Rose (Maine, USA) Wednesday 21st October 2009 Ahhh yes, the TRS-80 4P. I had one of these machines as my main computer in the mid/late 80''s. I used it to keep the books for my freelance software company as well as developed some software for it (mainly a Video renting system) in Model III mode. I have not-so-fond memeories of hauling this thing through various airports to make connecting flights. I think the only thing that made it portable was the handle in the case lol. It was seriously a very heavy ''portable'' machine. author date text Andy (Washington) Tuesday 20th June 2006 Well, went to my local Goodwill today and bought one of these babys for a smokin price of 5 bucks! Anyone interested in snaging this? /museum/radionic-model-r1001 /museum/sysdata-eletronica-jr /museum/tandy-radio-shack-trs-80-model-12 /museum/tandy-radio-shack-trs-80-model-16 /museum/tandy-radio-shack-trs-80-model-4 /museum/tandy-radio-shack-trs-80-model-i /museum/tandy-radio-shack-trs-80-model-ii /museum/tandy-radio-shack-trs-80-model-iii 1083 url date https://web.archive.org/web/20230608220843/http://www.old-computers.com/museum/computer.asp?c=1083 2023-06-08

The Model 4P was the transportable version of the Model 4.

Apart from the case and display sizes, technical features were almost identical to the Model 4's. The dual half-sized floppy drives were still single-sided versions but the keyboard, which slided underneath the computer, was far better than the one of the desktop version.

The external floppy drive connector was removed, as well as the Model 3 ROM, but a ROM image could be loaded from diskette to run Model 3 programs. An optional 300-baud modem could be also installed into the machine.

Very late models had double-sided TEAC drives.

---

Further information from Greg Trotter
I used a Model 4P for many years. It was pretty much identical to the Model 4 in functionality, except for:
- Portability, of course
- No Model III ROM (but you could load an image of the ROM into the RAM and reboot, giving perfect compatibility)
- It did have a modem card slot, except that the card edge provided power only; the outward face of the card had a short DC-25 serial cable, just long enough to get to the serial port of the 4P.
- There was no cassette interface on the 4P.
- The keyboard was indeed superior; I liked it better because it was corded and could be moved to any angle.

Of course, portable just meant "easier to transport." The entire unit weighed about 28 pounds, if I remember correctly. I lugged it through airports, and it fit quite comfortably in the overhead bin.