Sony SMC-70 Microcomputer
Introduced in 1982, the Sony SMC-70 is Sony's first 8-bit personal computer.It is arguably the first machine to use Sony's 3.5 inch microfloppy drive.
The SMC-70G is the exact same computer but with an NTSC video genlocker,
while the SMC-70GP has a PAL video genlocker.
The original target market was CAI (computer assisted instruction) and broadcast video.
The SMC-70 is a solid CP/M system, well-suited to general purpose use.
![[Photo]](sony_smc70_b.jpg)
My Sony SMC-70 and KX-8200CD monitor at the 2005 Trenton Computer Fest. (Photo by B. Degnan)
Frequently Asked Questions
Does it have any I/O ports?There are ports for:
Notes:
- Many of the DB25 connectors are keyed (one pin is blocked).
This was done to prevent you from accidentally plugging a cable into the wrong connector.- To boot from floppy, the Auto Start switch must be in the "Disk" position.
What kind of video monitor do I need?
You will want a monitor with analog RGB input and an appropriate video cable. These monitors can be difficult to find. The cables, even more so. Sony monitors I have used include: KX-1211HG, PVM-1270Q, KX-8200CD and KV-1311CR. I don't known the model number for any of the video cables, sorry.
There might be a way to rig up a composite video cable using the "B/W Multi Out" connector, assuming you can find the right plug. Looks like pin 8 is signal and 7 is GND.
Can I use it without a monitor?
You can connect a serial terminal to the RS-232C port.
Baud rate is set via DIP switch located under the floppy drives.
For example, switch 2 down selects 9600 baud.
There's also a handy little blue DCE/DTE plunger switch;
push it in to select "TERMINAL".
Finally, boot a CP/M floppy, wait until the floppy access LED goes out,
press enter a few times and type
STAT CON:=TTY:
Where can I get a boot floppy?
SMC-70 CP/M boot disk
(ImageDisk format)
Includes hardware-specific utilities BACKUP.COM, DIAG.COM and SETUP.COM
A: SETUP COM : BACKUP COM : SUBMIT COM : XSUB COM A: STAT COM : DDT COM : LOAD COM : PIP COM A: ED COM : ASM COM : DUMP COM : DUMP ASM A: DIAG COM : SAMPLE TXTCollection of utilities (ImageDisk format)
Includes Sony Disk BASIC and demo, QTERM, VDE editor, Rogue game, SMC-70 escape codes
B: BASIC COM : DEMO BAS : NS207 COM : NULU15 COM B: QT-DGSMC Z : QTERM COM : QTERM DOC : QTERM PAT B: ROGUE COM : ROGUE DOC : ROGUE NOT : SMC70ESC TXT B: UNARC COM : UNCR COM : UNCRLZH COM : UNSQ COM B: VDE COM
What kind of diskette media does it use?
Sony OM-D3320 or equivalent (SSDD 3.5" microfloppy),
either manual shutter or auto shutter.
In a pinch, you could probably use DSDD 720K media.
Are there peripherals for the Sony SMC-70?
Here's a (possibly incomplete) list of peripherals:
What is a cache disk?
The SMI-7050 Cache Disk is a 256KB RAM drive. You'd use it, for example, to speed up a compile. It's possible to use more than cache disk card, as long as each one is assigned a unique unit code, selected via a rotary switch below an access panel on the back of the card. Default unit code is 0. Use SETUP.COM to assign a drive letter.
How do I install or remove expansion cards?
Locate two large silver screws on either side of the floppy drives and loosen them. At the back of the machine, find the two small brass knobs and pull them our to extract a pair of "knitting needles" (for lack of a better term). Slide the power supply away from the rest of the system to expose the 3 expansioncard slots. Remove or insert cards. Slide the power supply against the cards, re-insert the needles and tighten the silver screws.
Can I read and write floppies on a different machine?
I've successfully used an MSDOS computer with a 3.5" drive, a program called 22DISK and this definition:
BEGIN SON1 Sony SMC-70 - SSDD 3.5" DENSITY MFM, LOW CYLINDERS 70 SIDES 1 SECTORS 16,256 SIDE1 0 1,4,7,10,13,16,3,6,9,12,15,2,5,8,11,14 BSH 4 BLM 15 EXM 1 DSM 135 DRM 127 AL0 0C0H AL1 0 OFS 2 ENDYou'll need to add the definition to 22DISK's database. For instructions on how to do this, refer to the 22DISK documentation.