website/content/museum/kaypro-4.md

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

title	categories	types	origins	years	cpus	params
Kaypro 4	Computers	Transportable	U.S.A.	1984	Z80A	name image logo company company_name specs tabs forum_thread photos links docs related oc_id source Kaypro 4 /media/museum/photos/kaypro_4_system_s1.jpg /media/museum/logos/kaypro_4_logo_s1.jpg /companies/kaypro Kaypro label value NAME Kaypro 4 label value MANUFACTURER Kaypro label value TYPE Transportable label value ORIGIN U.S.A. label value YEAR 1984 label value END OF PRODUCTION 1985 label value KEYBOARD Detachable, 72 key typewriter style keyboard with 18 programmable keys. label value CPU Z80A label value SPEED 4 Mhz label value CO-PROCESSOR Motorola 6845 (video controler) label value RAM 64 KB label value VRAM 2 KB label value ROM 2 KB label value TEXT MODES 80 chars x 25 lines label value GRAPHIC MODES virtual 160 x 100 through graphical characters label value COLORS built-in 9'' non-glare green phosphor screen label value SOUND No sound label value SIZE / WEIGHT 46 (W) x 41.5 (D) x 21.5 (H) cm / 15kg label value I/O PORTS Two RS-232C serial ports, one Centronics-type parallel port, communication socket (built-in modem) RJ11C modular telephone jack label value BUILT IN MEDIA two 5.25'' DS/DD half-height floppy drives (390 KB) label value OS CP/M 2.2 label value POWER SUPPLY Built-in power supply unit label value PRICE About $3500 photos links docs 542 title subtitle text image LARGE VIEW /media/museum/photos/kaypro_4_system_s2.jpg title subtitle text image SIDE VIEWS /media/museum/photos/kaypro_4_bothsides_s1.jpg title subtitle text image CLOSED When closed, the Kaypro rests on its keyboard. /media/museum/photos/kaypro_4_closed_s1.jpg title subtitle text image REAR PANEL **(1)** Reset switch\ **(2)** Phone cord RJ11 connector\ **(3)** Parallel printer connector\ **(4)** First serial port\ **(5)** Second serial port intended for a serial printer\ **(6)** Keyboard RJ11 connector\ **(7)** Display brightness knob. /media/museum/photos/kaypro_4_rearpanel_s1.jpg title subtitle text image OPENED All the Kaypro series - from Kaypro 1 to Kaypro 16 has the same internal layout. /media/museum/photos/kaypro_4_opened_s1.jpg title subtitle text image MOTHERBOARD **(1)** Signetics 6545 video chipset\ **(2)** 2 x Z80 SIO chips in charge on one serial port each\ **(3)** Built-in modem circuitry\ **(4)** Real-time clock IC (MM58167) powered by the rechargeable battery that is soldered on the board\ **(5)** Zilog Z80 PIO in charge of the parallel interface\ **(6)** Western Digital floppy-disc controller chipset\ **(7)** Zilog Z80A processor\ **(8)** System ROM. Allows the system to load the OS from the diskette when switched on\ **(9)** 64 KB user RAM (8 x 4164)\ **(10)** Custom chip dedicated to the memory management\ **(11)** 4 KB Video RAM chips (2x2116)\ **(12)** Character generator ROM /media/museum/photos/kaypro_4_mainboard_s1.jpg title subtitle text image DISMANTLED Dismantling a Kaypro computer is quite easy, provided that you carefully write down the location of each connector and the way they are connected. /media/museum/photos/kaypro_4_dismantled_s1.jpg title subtitle text image MANUALS Kaypro shipped its computers with a large bunch of software and manuals. /media/museum/photos/kaypro_4_manuals_s1.jpg title url text Web Wiz CAPTCHA http://www.webwizcaptcha.com title url cover text KAYPRO TECHNICAL MANUAL null /media/museum/docs/couvs/kaypro_technical_manual.jpg **KAYPRO TECHNICAL MANUAL**\ written by Kaypro  compiled/archived by Unknown\  type of document : Online reader **... READ THE ONLINE VERSION BY CLICKING BELOW :** /museum/kaypro-1 /museum/kaypro-10 /museum/kaypro-2x /museum/kaypro-ii /museum/kaypro-iv /museum/kaypro-robie 548 url date https://web.archive.org/web/20230329011529/http://www.old-computers.com/museum/computer.asp?c=548 2023-03-29

This is the Kaypro 4 released in 1984, usually refered as Kaypro 4/84, as opposed to the Kaypro IV released one year earlier, and refered as Kaypro IV '83.

The main differences between the Kaypro 4 '84 and the Kaypro IV '83 were :
- A faster CPU, Zilog Z80A running at 4Mhz,
- A real time clock which can be used by programs (uses National MM58167),
- A better built-in monitor resulting in a very sharp display. The character matrix has also evolved from 5 x 7 on the Kaypro II and IV '83 to 8 x 16 pixels on the Kaypro 4 '84,
- the system had rudimentary graphics through graphical characters resulting in a virtual 160 x 100 resolution,
- characters could be displayed using two brightness levels and reverse attribute,
- the new prompt was a blinking square,
- like on modern keyboards, J and F keys were slightly different in shape from the other keys, so it was possible to spot them while staring at the screen,
- there was a built-in modem (300 baud, Bell System 103 compatibility, uses Texas Instruments TMS99537/TMS99532),
- the system had two DS/DD half-height floppy drives (390 kb)

The system was bundled with Wordstar, dBase II, MicroPlan, Microsoft Basic, S-Basic, SuperCalc, C-Basic and CP/M 2.2 !

In 1984, in order to be compatible with IBM software, a special version was marketed with an Intel 8088 CPU in addition of the Z80A. It was called Kaypro 4 Plus 88!

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Walter J. Dickie reports:
The Plus 88 was a dual-processor machine. First you booted up in CP/M, then inserted an MS-DOS (not PC-DOS) disk and booted the 8088. The really slick thing about the Plus was that in CP/M you could run the 8088 and it's associated 256K of RAM as a ramdisk. My standard boot routine involved booting in CP/M, firing up the 8088 as a ramdisk, copying all the WordStar overlay files onto the ramdisk (they just fit), then running WordStar on the Z80. With WordStar calling its overlays from the ramdisk the damn thing just flew!