====== Tandy/Radio Shack TRS-80 Model 4 (1983) ======
===== Features =====
* CPU: Zilog Z80 4 MHz
* RAM: 64 KB (up to 128 KB)
* ROM: 14 KB
* Text Modes: 64 x 16 / 32 x 16 / 64 x 40 / 80 x 24
* Graphic Modes: None
* Colors: Monochrome green phosphore
* Sound: Built-in speaker
* I/O Ports: Tape (500 or 1500 bauds), Centronics, I/O ports compatible with Model III, Serial (4D)
* Keyboard: Typewriter style 83 keys with numeric keypad
* Built In Media: One or Two 5.25" disk-drives
* OS: TRSDOS 6.0 or 1.3, LDOS, CP/M
* Built In Language: None
===== Known Issues =====
Notice that this system is a TESTDRIVER, i.e. it's not included in the pre-compiled MESS you find at mess.org -- http://www.mess.org/.
===== History and Trivia =====
The TRS-80 model 4 (ref 26-1068/69) was one of the last models of the TRS-80 series (and perhaps the less known). It ran at 4 MHz and displayed 80 columns x 24 lines in Model 4 mode, but was fully compatible with the TRS-80 model 3 and in Model 3 mode actually displayed 64x16 and ran at the Model 3's 2 MHz.
It had 64 or 128 KB RAM, the 64 upper KB being used as a ram disk. It had one or two 5.25" floppy disk (184 KB each) and ran under TRSDOS 6.0 or 1.3, LDOS or CP/M.
A transformation kit "TRS80 model III -> model IV" was available.
The Model 4 was followed by the Model 4D (ref. 26-1070). The only difference being double sided drives -384 KB, instead of single sided drives.
A portable version of the Model IV called Model 4P (ref. 26-1080) was also marketed few time after.
//(info from old-computers.com)//
===== Links =====
* Ira Goldklang's Page -- http://www.trs-80.com/
* Timm Mann's TRS-80 Page -- http://www.tim-mann.org/trs80.html
* TRS-80 Model 4 at old-computers.com -- http://old-computers.com/museum/computer.asp?c=244
===== Other Emulators =====
* David Keil's TRS-80 Model III/4 Emu -- http://discover-net.net/~dmkeil/trs80/model1.htm
* Jeff Vavasour's TRS-80 Model III/4 Emu -- http://www.vavasour.ca/jeff/trs80.html#model4
* TRS32 -- http://www.arrowweb.com/mkr/
Generated on Sun Jul 19 10:17:28 2009