Commodore plus 4 Error

[Ranger03]

I was browsing through the Plus 4 reference manual (page 18) and tried the graphics example and i have 2 questions:

 

1. I get errors in 40, 50 and sometimes 30 about illegal quantities, despite the fact that i am entering it as written

 

2. Why does the Plus 4 get so much hate? i believe that it is a decent attempt. The Basic is much improved for starters.

[Casey]

If you are talking about the 5 line example program in this book on page 18 - it works as written.

 

https://ia801709.us.archive.org/8/items/Programmers_Reference_Guide_for_the_Commodore_Plus_4_1986_Scott_Foresman_Co/Programmers_Reference_Guide_for_the_Commodore_Plus_4_1986_Scott_Foresman__Co.pdf

 

If not, you'll need to be more specific about which manual you are looking at.

[carlsson]

Note that it really should be BOX, as the comma is not a typo, it just omits a parameter to default colour.

[Ranger03]

If you are talking about the 5 line example program in this book on page 18 - it works as written.

 

https://ia801709.us.archive.org/8/items/Programmers_Reference_Guide_for_the_Commodore_Plus_4_1986_Scott_Foresman_Co/Programmers_Reference_Guide_for_the_Commodore_Plus_4_1986_Scott_Foresman__Co.pdf

 

If not, you'll need to be more specific about which manual you are looking at.

the manual you just linked to. I keep getting an illegal quantity error

[Casey]

yes. As listed in the book, that program works correctly. Check for typos and make sure you typed it exactly as listed. As carlsson stated, line 40 starts with BOX, complete with comma.

[Ranger03]

I typed page 18 as stated and got an illegal quantity error in 40. Before you accuse me of trolling, understand that i have checked everything that might've caused the issue. If you want, i can upload a recording but i don't think that will be necessary

Edited August 31, 2018 by Ranger03

[Ranger03]

Note that it really should be BOX, as the comma is not a typo, it just omits a parameter to default colour.

 

i didn't notice the comma before the rest. thank you for your help. as to why it is so slow in vice 3.2, i have no clue

Edited August 31, 2018 by Ranger03

[Casey]

Then you've typed it in wrong. I literally just typed it into the Plus/4 emulator and it worked.

[Arnuphis]

...The ZX Spectrum is easier to work with

 

Here we go again....

 

 

Oh and I also typed that page 18 circle program in just for curiosity's sake and it worked fine. The problem lies with your input.

Edited August 31, 2018 by Arnuphis

[Ranger03]

Then you've typed it in wrong. I literally just typed it into the Plus/4 emulator and it worked.

i just said that i got it to work. i figured out the problem thanks to carlsson and rectified it

[carlsson]

Well, one problem less in the world. For that matter ZX Spectrum BASIC doesn't even have a built-in command for drawing boxes, just dots, lines and circles.

 

Yes, VICE 3.x is even more exact than earlier versions which manifests on weaker hardware by running slower. I don't know if it can be configured to be less precise to increase execution speed, though that seems counter intuitive to what the emulator tries to achieve. Those fast and approximate simu-emulators of the 1990's mostly are a thing of the past now. They were good enough for testing out things like BASIC but could misbehave badly if running advanced machine code programs that rely on exact timings.

[TMR]

2. Why does the Plus 4 get so much hate? i believe that it is a decent attempt. The Basic is much improved for starters.

I wouldn't say it gets a lot of "hate" but calling it a "decent attempt" implies that you haven't really looked at what the hardware offers... or more appropriately doesn't offer. Many of the machines released before them like the Atari 8-bit or C64 offer more features; the C64 alone has eight very good hardware sprites and the SID chip, the Atari's got four large and four small hardware sprites (unsupported from BASIC, so you'll have to use lots of POKEs for them) while POKEY is four channel sound with some useful options and the 264 series have to do sprites in software (without a major boost in CPU grind to make up for that omission and good luck getting that to work smoothly from BASIC) and get a couple of tone generators. No filters, no ring modulation, not much of anything really.

 

The BASIC being improved is, for the majority of users including the majority who wanted to do anything more serious than dabble with programming, pretty much an irrelevance...

[Arnuphis]

Some good stuff in the above post. A quick google search would tell you why the TED series of computers was not well received so no need to really recycle the reasons here. Another thing to realize is that flip flopping between commodore emulation options also doesn't tell you much about the actual machine experience itself(maybe that is why you think the Spectrum is so amazing? If you sat down with the actual original Spectrum and tried to use it you'd probably have a lot of different things to say).

 

Commodore did away with the standard 9 pin Atari joystick interface on the Plus/4 in favor of a smaller round one. Same for the Datasette port. So people coming from an earlier model had to buy those things again or buy an adapter. The 1551 drive was great but there was little software to run on it. The built in software was crippled by the amount of resources allowed for it. Plus the TED chip liked to self destruct which is why getting an actual working one today is not that easy.

 

In all it was a bit of a disaster which was rectified by the release of the 128. I had a Plus/4 back in the day and although I made good use of it I ended up selling it and going back to a C64.

Edited August 31, 2018 by Arnuphis

[carlsson]

The Plus/4 never was intended to be an upgrade or alternative to the C64. It was meant as an ultra cheap introductionary computer, and in the end came to replace the VIC-20 on the low end, though it cost as much or more than a C64 so that part was a bit confusing too.

 

The C116 was planned to be sold for $49 but I believe eventually was released closer to $69 or $79 (converted from D-Mark, as it was very rarely seen in the US anyway). Under those circumstances, perhaps it was a decent attempt. For people expecting an improved C64, it definitely was not a decent attempt.

[TMR]

The Plus/4 never was intended to be an upgrade or alternative to the C64.

Commodore might not have intended that, but the two machines were competing for new users in roughly the same market space with other 64K systems of the time. This is just the kind of Commodore marketing "logic" that saw them insisting the CDTV wasn't displayed within a certain distance of Amiga computers...

 

It was meant as an ultra cheap introductionary computer, and in the end came to replace the VIC-20 on the low end, though it cost as much or more than a C64 so that part was a bit confusing too.

The whole range was confusing to consumers; nobody seemed to know if it was an upgrade, meant to replace another Commodore product or which model they actually wanted/needed.

[BassGuitari]

I'd like my Plus/4 a lot more if it actually worked.

[Ranger03]

no tape compatibility. that's just mean

[Arnuphis]

Yep as Carlsson said, it was meant to be a sub $100 computer to win the entry level market. Like the Amiga 600 it ended up being sold in the wrong price range and crashed and burned.

[TMR]

no tape compatibility. that's just mean

It has tape, just using a different connector because presumably the standard DIN was cheaper than a bespoke edge connector... and there are convertors to put a C64/VIC/C128 deck onto a C16 or Plus/4 as well.

[carlsson]

I think the change of connectors were due to three reasons:

 

1. Save board space, supposedly the mini-DINs have smaller footprint than both the edge connector and DE9 for joysticks. This made sense on the C116, and ideally it would be even smaller than it is.

 

2. Electrically more safe, according to Commodore sources. That means female mini-DINs on the computer side are less likely to be prodded by fat fingers, shorting something. I don't know if this really is a problem.

 

3. Temporarily shut out 3rd party manufacturers, give Commodore a head start in selling peripherals. While it never was an official explanation, this one weighs a lot to me.

[TMR]

2. Electrically more safe, according to Commodore sources. That means female mini-DINs on the computer side are less likely to be prodded by fat fingers, shorting something. I don't know if this really is a problem.

Well, the joystick ports possibly not - although all those people licking their fingers and rubbing the pins of port 1 for the cheat mode on Creatures 2 was always a worry - but I do remember booking in quite a few C64s for repair where the tape deck's earth lead snuck into the user port or someone had tried resetting with a straightened paperclip and shorted the wrong pins.

 

3. Temporarily shut out 3rd party manufacturers, give Commodore a head start in selling peripherals. While it never was an official explanation, this one weighs a lot to me.

That's probably true of course but I'd assume it was more of a side benefit rather than a primary motivation; I don't think particularly highly of Commodore at that point from a business perspective but their engineers would've had something to say if the decision were forced on them from above and, to date at least, nobody has done so that I'm aware of...?

[carlsson]

There is also the question if Atari held a patent for the joystick port pinout or not, and if they tried to enforce it if they did. I'm unclear on this, but it could be one more reason to change the connector, to avoid Atari. However as Commodore went back with the DE9 for the C128, either they settled something or the threat never was there. As for electrically more safe, apparently the C128 doesn't need those precautions as it has the same ports as the C64.

 

While I don't have a specific message to link to, I believe Bil Herd has addressed the TED and Plus/4 range a number of times, various design decisions and not. I know as much as the TED developer board which I still own (stamped August 1983), has both the card edge tape connector and DE9 joystick ports, and while it might not fit into a C116 case, it surely is smaller than a regular VIC-20 or C64 board.

Edited September 6, 2018 by carlsson