Working on a couple of SMC-70s

[markgm]

You are right that "in the real world no one booted this thing into ROM BASIC". The main reason for this is that the target audience for the SMC-70 was primarily the business and professional video production sector.

The SMC-777, which appeared later, was intended for beginners, hobbyists, and home users and did not have a built-in ROM BASIC, which distinguishes it from the SMC-70.

As for other differences between the two machines, the SMC-777, apart from the built-in ROM BASIC, omitted the bus expansion slots, which significantly reduced the expansion capabilities, but this was done to reduce costs and make the machine more accessible to hobbyists. However, it did come standard with a single built-in floppy drive.

In terms of shared features, both systems used the Z80A CPU and 64 KB of RAM and had 3.5-inch micro-floppy disk drives, where the later version of the SMC-777 (i.e. the SMC-777C) further improved the capabilities in terms of color and gaming.

I came across information that the SMC-70 came with a demo program on an audio cassette (does anyone still have it?) that demonstrated the capabilities of the device. I can assume that the only way to boot this cassette was from the built-in ROM BASIC, which is another reason why it would have been good to have it.

For other interesting information, I would recommend everyone to read the article from the link Obsolete Sony's Newsletter: The Birth of Sony Computers.

Cheers

I'm not quite sure what you mean with the first part of your post when you compare the 70 with the 777. It would seem that it would have made more sense to put ROM BASIC on the 777 than on the 70 (hobbyists would have been more likely to use it than business users). I think the real reason they shipped the SMC-70 with ROM BASIC was Sony sold it without the disk controller/disk drive(s), though I have never seen anyone use one in that configuration (I'm sure some folks did, when it was released 2 floppy drives cost around the same price as the base computer).

A small correction, the SMC-70 was for general business use, while the SMC-70G was for video production, though the entire line (70 through 777C) was highly compatible with each other, and software and peripherals from the former would work on the latter. To that end, the 777 still had the same expansion bus (with a single internal port), and with the disk controller now integrated, it needed one fewer internal port. As you mentioned, it didn’t have the bus expansion slots (there were 3 on the SMC-70, 4 on the SMC-70G), but it did have the bus connector on the rear that would accept the SMI-7040, which added 5 additional slots to any of the computers.

I have the tape deck, but I have never found the demonstration cassette (I wonder if it only went to dealers). The only cassette program I have ever seen was char.bas included with the emulator. I assume the demo.bas program is the same one included with Sony BASIC, though I am curious what the golf program is. I don’t think software was ever released in the US on cassette (don’t quote me on this, though I’ve never seen any). My guess was the cassette option was included for potential home use (there were games released in Japan on cassette; Battle Hanafuda from Dempa was one I know existed), but part of the appeal of the machine was how cutting edge it was (though floppies at $5 a piece was the price to pay for being cutting edge, or ~$17 today).

 

[alexsal]

I'm not quite sure what you mean with the first part of your post when you compare the 70 with the 777. It would seem that it would have made more sense to put ROM BASIC on the 777 than on the 70 (hobbyists would have been more likely to use it than business users). I think the real reason they shipped the SMC-70 with ROM BASIC was Sony sold it without the disk controller/disk drive(s), though I have never seen anyone use one in that configuration (I'm sure some folks did, when it was released 2 floppy drives cost around the same price as the base computer).

I guess at the time the SMC-70 came out, it was normal for a computer to have ROM BASIC built in, as did computers from other manufacturers: NEC, Fujitsu and others, to name a few, and also, as you mentioned, it came without a built-in disk drive. Whether anyone used it or not I don't think is important. The IBM PC also came with built-in ROM Basic, so did anyone use it?

For the SMC-777, which came standard with a built-in disk drive and used Sony's own operating system, "Sony Filer", which already had a version of BASIC built in, installing ROM BASIC really didn't make sense anymore.

A small correction, the SMC-70 was for general business use, while the SMC-70G was for video production, though the entire line (70 through 777C) was highly compatible with each other, and software and peripherals from the former would work on the latter. To that end, the 777 still had the same expansion bus (with a single internal port), and with the disk controller now integrated, it needed one fewer internal port. As you mentioned, it didn’t have the bus expansion slots (there were 3 on the SMC-70, 4 on the SMC-70G), but it did have the bus connector on the rear that would accept the SMI-7040, which added 5 additional slots to any of the computers.

Thanks for the correction!

---------

I found another difference between the SMC-70 and the SMC-777:

According to the SMC-70 Computer Museum the computer had 4 graphics options:

160 x 100 pixels, four panes (16 colors)
640×200 pixels (4 colors)
320×200 pixels (16 colors)
640×400 pixels (B&W)

While according to the SMC-777-Computer Museum this computer had only two:

640×200 pixels (4 colors)
320×200 pixels (16 colors)

 

[alexsal]

I have the tape deck, but I have never found the demonstration cassette (I wonder if it only went to dealers). The only cassette program I have ever seen was char.bas included with the emulator. I assume the demo.bas program is the same one included with Sony BASIC, though I am curious what the golf program is. I don’t think software was ever released in the US on cassette (don’t quote me on this, though I’ve never seen any). My guess was the cassette option was included for potential home use (there were games released in Japan on cassette; Battle Hanafuda from Dempa was one I know existed), but part of the appeal of the machine was how cutting edge it was (though floppies at $5 a piece was the price to pay for being cutting edge, or ~$17 today).

Since you have a tape deck, and in case you didn't know, the Inufuto site has a collection of free retro PC games, which also includes games for both the SMC-777 as a disc image in .1dd format and the SMC-70 as a cassette in .wav format.

Games intended for the SMC-70 are launched from ROM BASIC with cload"" and run. Here's the chance to test the tape deck and see if it works.

I'm not sure, but I assume that games intended for SMC-777 in .1dd disc format could work on SMC-70 too!?

 

[alexsal]

The SMC-70 and the SMC-777 are very similar units software wise, and some of the software will work on both. Might help you in your search for programs.

As for compatibility, I came across something here that works fine on the SMC-70 but not on the SMC-777.
It is a DEMO program that is started from BASIC and is located on the second disk called "smc70util". (and which is not on the smc777 soft list!)

So, put the first disk "smc70cpm" in drive A: and the second disk "smc70util" in drive B: and start the computer.
When the A: prompt appears, change it to the B: and load BASIC from there, or if there is only one drive, leave it in the A: prompt and just swap disks.

When BASIC has started, start DEMO from it with RUN"DEMO" or write DIR and go with the cursor up to the name "DEMO.BAS" before which you write RUN and press enter.

As we can see here on Takeda's website, starting from the date "2019/1/18", the mentioned DEMO works without problems in eSMC-70 emulation, but if it is tried in eSMC-777 emulation there are some display problems (same on WinSMC017 emu or the latest MAME 0.288 smc777 driver), which suggests that the DEMO is not intended for SMC-777 machines. (which also means, a great test case for the smc70 driver in some future MAME version)

Also, on arhive.org I came across some software catalogs for the SMC-777 and SMC-70: Software catalog 1983-10 and Software 3 Catalog.
There is some software list on the "Mysterious Software List" as well.

And also some interesting catalogs of the hardware itself: Hit Bit Catalogue 1983-11 and Hit Bit Catalog 1984-05.

Cheers

EDIT: Just to mention that the MAME smc777 driver has been greatly improved in the latest version 0.288! (so maybe it is probably the best emulator for this machine at the moment)

 

[markgm]

Since you have a tape deck, and in case you didn't know, the Inufuto site has a collection of free retro PC games, which also includes games for both the SMC-777 as a disc image in .1dd format and the SMC-70 as a cassette in .wav format.

Games intended for the SMC-70 are launched from ROM BASIC with cload"" and run. Here's the chance to test the tape deck and see if it works.

I'm not sure, but I assume that games intended for SMC-777 in .1dd disc format could work on SMC-70 too!?

Many SMC-777 games will work on the SMC-70, it's usually dependent if the game requires the additional color palatte available on the SMC-777.

I don't have an SMC-777 to test if the actual Sony Disk BASIC demo from the SMC-70 would run on an SMC-777, but I know there were a few challenges getting it running smoothly on any emulator (I was one of the folks providing feedback to Takeda). One interesting side effect running the demo on the 777 emulator is it shows BUG BASIC during the opening screen, which I am guessing is an Easter egg from BUG, the company that wrote Sony's BASIC. One reason it might not work on actual 777 hardware is that the SMC-70 supported a high resolution black and white mode (in the demonstration program it's the box drawing portion of the program), and I don't believe the SMC-777 supported this mode; monochrome 640x400).

Bob Saito has a great list of software on his smc777 site (I think he might here). A few years ago we started putting together a comprehensive list, I just need to get around to putting it all together and publishing it.

Thanks for the link on the games, I will give them a try! I hadn't come across those wave files before.

 

[alexsal]

I did a test in the Takeda eSMC70 emulator!

I tried to load Inufuto aerial.wav (tape file for SMC-70) from Disk-BASIC (from "smc70util") with cload""... it said "FOUND : AERIAL .BAS" and threw the error "Error (140) : Invalid format". (see the red frame in the picture)

Then I wrote some test program in Disk-BASIC and saved it with csave"TEST". When loading that test program with cload"" it did not throw an error. (see the green frame in the picture)



Now, is this a bug in the emulator that only recognizes its recorded tape format or would it throw the same error on a real machine if the Inufuto game was tried to be loaded from Disk-BASIC ?

If we had that missing ROM BASIC we could test whether it loads it in the emulator from it or not and whether there is some incompatibility between ROM BASIC and Disk-BASIC regarding the recorded tape format.
(which it shouldn't, because how would a user transfer their BASIC programs written in ROM BASIC to disk?)

Also, it might be a good idea to test the same thing on a real SMC-70 machine to be sure what it is.

P.S. When loading Inufuto aerial.1dd (disk for SMC-777) into eSMC70 emulator, it works but there is a problem with control, while in eSMC777 emulator there is no problem when using joystick in port #1.

 

[markgm]

Oddly, I can get it to load in ROM BASIC in the emulator, but the system locks up when I try to do anything else. I get the same error you do in disk BASIC.

 

[alexsal]

In the SMC-777 GuideBook on p.240 it says what the difference is between the SMC-70 and the SMC-777... (quote translated by Google translate)

5) The relationship with SMC-70

The SMC-777 is hardware-compatible with the SMC-70. You can even insert the CP/M disk from the SMC-70 and run CPM on the SMC-777. However, there are a few differences, the main ones being as follows:

- Graphics modes 160x100, 640x400 are gone.
- While the SMC-70 could accommodate 32K byte shadow ROMs in its socket, the SMC-777 could only accommodate 16K byte shadow ROMs.
- The calendar clock and light pen interface are gone.

EDIT: I would also add that the SMC-777 has two Joystick ports, while I'm not sure if the SMC-70 has any at all.

That's why the SMC-70 demo freezes at the very end at the clock display when running on the SMC-777 emulator because the time$ variable is not supported.

Also, when you write: print time$ from SMC-777 BASIC on a eSMC777 emu, an error is thrown: "Error (152) : Function not available"!

The same error is printed on the eSMC70 emu if SMC-777 BASIC is started, but from CP/M Disk-BASIC time$ and date$ work without problems.

P.S. There's a video of "Sony SMC-70 Demonstration Program" running on a real SMC-70 machine! (so it can be compared with the eSMC70 emulator)

------
@markgm
Thanks for checking! Strange that it doesn't work on the eSMC70 emu even when booted from ROM BASIC! (but it works on a real machine, right?)

 

[markgm]

That's my video . You are correct, the SMC-70 has no joystick ports, though there was an expansion to add them (not made by Sony as far as I'm aware). I did read something about someone putting an SMC-777 ROM in an SMC-70 to make it more compatible with SMC-777 software, and using a jumper on the SMC-70 to swap between the two (https://www.asayan-town.com/retro-pc/smc-70/). This seemed odd to me though, because both of my ROM slots are occupied (and are on every SMC-70/70G I own). I wonder if this was something that was done for systems in another country, because I also don't have the jumper header (but the solder markings exist on the motherboard). Both of my ROMs are 128kbit, while this person mentions having an empty socket because Sony might have gone with using 2 64kbit ROMs instead. It just seems odd that somehow Sony would have been able to eliminate one of the ROMs in another region (unless Sony shipped those with a 256 kbit ROM, which I guess would be more likely, but that's not what his picture shows). I wonder if people just pulled the second ROM and lost Sony BASIC. One of Sony's own marketing photos shows the board with a single ROM chip.

I didn't have any luck finding a copy of volume 3 of Oh! Hit Bit, but if I ever come across one, I'll have to check out what they say about the "SMC-77" to see why someone would have wanted to do it (maybe it just faked the color palette to make software run.

Out of curiosity I tried an earlier ROM (1.00) and loaded up the games in ROM BASIC from cassette, and while they still don't work, out of 5 of them, 2 of them get to the title screen before locking up (the others lock up immediately).

 

[alexsal]

That's my video . You are correct, the SMC-70 has no joystick ports, though there was an expansion to add them (not made by Sony as far as I'm aware). I did read something about someone putting an SMC-777 ROM in an SMC-70 to make it more compatible with SMC-777 software, and using a jumper on the SMC-70 to swap between the two (https://www.asayan-town.com/retro-pc/smc-70/). This seemed odd to me though, because both of my ROM slots are occupied (and are on every SMC-70/70G I own). I wonder if this was something that was done for systems in another country, because I also don't have the jumper header (but the solder markings exist on the motherboard). Both of my ROMs are 128kbit, while this person mentions having an empty socket because Sony might have gone with using 2 64kbit ROMs instead. It just seems odd that somehow Sony would have been able to eliminate one of the ROMs in another region (unless Sony shipped those with a 256 kbit ROM, which I guess would be more likely, but that's not what his picture shows). I wonder if people just pulled the second ROM and lost Sony BASIC. One of Sony's own marketing photos shows the board with a single ROM chip.

I didn't have any luck finding a copy of volume 3 of Oh! Hit Bit, but if I ever come across one, I'll have to check out what they say about the "SMC-77" to see why someone would have wanted to do it (maybe it just faked the color palette to make software run.

Interesting and thanks for the info. Yeah, it would be nice if we could find that Oh! Hit Bit Volume 3 and see if it mentions any SMC-777 titles that cause incompatibility with the standard SMC-70 ROM, but work with the 777 ROM.

P.S. I guess then maybe, regarding the less compatibility, the reverse would also be true, with the SMC-70 ROM on the SMC-777 computer (or emulator)!?

Out of curiosity I tried an earlier ROM (1.00) and loaded up the games in ROM BASIC from cassette, and while they still don't work, out of 5 of them, 2 of them get to the title screen before locking up (the others lock up immediately).

I wonder if the version of the shadow ROM used could also cause this problem because if the eSMC70 emu uses one of the shadow ROMs from the MAME smc777 driver ("1st rev." or "2nd rev.") instead of one from a real SMC-70, I wonder if that could also be the reason why it doesn't work?

 

[alexsal]

There is a Creative Computing benchmark that was used to compare the performance of the BASIC programming language on different machines: --> https://en.wikipedia.org/wiki/Creative_Computing_Benchmark

I tested the Takeda's eSMC-70 emulator in Disk-BASIC with the original version of the benchmark from the November 1983 edition...



... and got the same results that appeared in its last appearance that was in the May 1984 issue:



So, it can be said that the eSMC-70 emulator is quite accurate.

Note: In the magazine, all "random" results are rounded to one decimal place!

 

[markgm]

Curiously, it runs in ~1.31 seconds in ROM BASIC (with the same results otherwise); I'll have to try this on actual hardware.