Re-entering Basic on VInce Briel/Reactive Micro APPLE one Replica Plus

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Re-entering Basic on VInce Briel/Reactive Micro APPLE one Replica Plus
  I am typing E2B3R as instructed by the manual and the machine refuses to do anything. Keeps getting stuck at e2b3: 05 and blinking funny at me. Not sure what to do here. UPDATE: Upon repressing reset and retyping the command a few times it will reload into basic. Am i being dumb or is that just how it works?                                                                                              UPDATE 2: It usually has a higher success rate if i hold down the reset button. On top of this, the basic program will not run correctly. It will instead do random things.
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cold vs warm start addresses

The program that reads your input when you type "E2B3R" is called the Woz Monitor or Wozmon for short. The full monitor program is squeezed into just 256 bytes, so it has a few idiosyncrasies. One of them is its prompt, which is a backslash followed by a linefeed.

The monitor responds by printing the byte at the address E2B3, and then using the same address again as a machine code address to execute. That behavior can be confusing, but it's another of the idiosyncrasies that Wozmon users must learn to live with.

Whatever happens next depends on what the code at that address does.

On a real Apple I, you have to load Apple BASIC through the cassette interface. On Briel's Replica I, Apple BASIC is in ROM at E000-EFFF. So all machine addresses starting with "Exxx" are part of BASIC's code.

The machine code address E2B3 is called the "warm start address". It is used to return to the BASIC prompt (>) after stopping in the Monitor. But this entry point leaves the BASIC program and data intact; if you had typed in a BASIC program, it will still be there and you can still RUN it.

When you first start the machine, there is no program in memory, but random data instead. Because Wozmon is so short, it does not have any code to clear memory or initialize it. The result is that if you go directly to E2B3, BASIC will think that the random data is your program, and will crash.

The proper way to get to BASIC when starting the machine is to use the "cold start address", which is E000. It has code to initialize some critical data structures (such as the pointers to the start and end of the memory range of your BASIC program).

See also here.

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The problem

 

More clarification needed please.

For reference, i have posted exactly what I am doing here:

 

STEP 1: E000R (E, three zeros, and an R) ( this loads basic)           

STEP 2: Write hello world program                   

STEP 3: Hit reset button   (leaving basic for testing purposes)                                               

STEP 4: E2B3R (re-entering basic)

STEP 5: Result is e2b3: 05@ (the @ symbol blinks and the computer fails to do anything)                                                                                                                                                                                                                                           

Have a great rest of the day! -Kenopsias                                                                                                                                                       

 

UPDATE: Going to address E2BEr allows me to re-enter basic just fine.  Step 5: press E2BER (gives message E2bER: 03. Next line is ?no for err. Last line loads up basic command line. Upon running list command it recites list and the program can run)                                                                                                                                                                                                                                                                                                                                         

UPDATE 2: I am struggling with reloading a program from cassette. When reloading the program, I enter via E2BER as described in this post, when running the list function it gets stuck or has problems. Do you have any advice?          

 

UPDATE 3: I have noticed a rom selector for applesoft basic = on and integer basic = off. Which basic should I choose and how?

 

 

 

 

 

 

 

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Use Apple Basic

All of the software for the Apple I uses Apple Basic, which was the forerunner to Integer Basic on the Apple II.

The Replica I can also use something called Applesoft Lite, but the programs you can download are not compatible with it.

I haven't read the Applesoft Lite documentation, but its warmstart entry point may be a different address.

Edit:

I can see the source:

; ----------------------------------------------------------------

; WARM RESTART ENTRY

; COME HERE FROM MONITOR BY CTL-C, 0G, 3D0G, OR E003G

; ----------------------------------------------------------------

Looks like that answers that.

This looks a lot like Applesoft Basic on an Apple II+ (or later), where you can go from Basic to the Monitor with CALL-151, and from the Monitor you can either type E003G to warmstart (your Basic program remains intact), or E000G to coldstart (your Basic program is cleared).

The Apple I Monitor is at a different address, so the command to enter it from Basic is CALL-230 instead of CALL-151.

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 I could be wrong but I am

 I could be wrong but I am almost certain integer basic was for the apple one where as applesoft basic was for the apple 2 and only later was integer basic imported to the apple

https://en.wikipedia.org/wiki/Integer_BASIC

 

 On top of that, I still need to know how to load and save to cassette as that is what i appear to be struggling with. All of the relevant literature doesn't seem to work on my Replica One.         

 

I will continue to play around with the machine but any advice concerning why im having difficulty loading programs onto the Replica One would be most helpful.

 

Once again the help is much appreciated! 

-Kenopsias  

 

 

 

 

 

 

 

 

 

 

 

 

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Basic version history

No, Integer Basic is in ROM on the Apple II. Applesoft Basic was in ROM on the Apple II Plus. The II and II+ have identical hardware: they differ by which version of Basic is in ROM, as well as whether the original or Autostart Monitor is in ROM.

Applesoft (Apple + Microsoft, get it?) uses floating point arithmetic between -10^38 and 10^38. Integer Basic uses integer arithmetic between -32767 and 32767.

Either a II or a II+ can switch between the two Basics if it has a Language Card installed. This is done with the FP and INT commands.

 

The "Applesoft Lite" is a modern invention and was never available on historical Apple Is. None of the Apple I software makes use of it. The Apple I had only Apple Basic (which was the predecessor to Apple II's Integer Basic), and had to load it from cassette.

 

Does the Replica I even have a cassette port? It has a serial terminal, so you can upload programs to it very easily using Minicom or another terminal program. The Apple I cassette port never actually worked reliably, so I would simply forget using it.

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It does not natively have a

It does not natively have a cassette port. You have to install an Apple Cassette Interface in the Replica One's singular card slot which is what I have done. There are programs for it and ways to save to cassette but I am struggling with it as I am doing something wrong but am unsure of what. When following the directions verbatim, the computer does strange things.

  

Have a great day! 

  -Kenopsias

 

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Be careful with shift and

Be careful with shift and caps lock keys on the r1plus. IIRC, sometimes you can make a character display that isn't processed as part of the address.

 

I use an Appledore adapter with c64 keyboard for retro feel and it eliminates this issue. The plab high speed ascii terminal eliminates it as well.  

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Problems with ACI ?

As a general rule, when using the ACI, always type all four digits of all hexadecimal numbers (addresses). If you type less than four hex digits, all addresses other than the first one on the command line will be internally wrong and have leftovers from any previous address typed.

 

This is a bug / pitfall in the ACI firmware as written by Woz. For my extended formatting PROMs, I decided not to touch his code at all, but use his command line parser, so the bug is still there. But it can easily be avoided.

 

As 'skate323k137' has correctly stated in post #8, the keyboard codes must be right because the firmware makes certain assumptions, like MSB always being set, and no lowercase, and no special characters other than ESC and RETURN allowed.

 

All my improved ACI versions (Gen 1 and Gen2) have been used successfully with Briel Replica-1 and were reported to work fine. So there is no reason why  you have problems if proper procedure is followed (i.e. proper adjustment of the volume). Keep the tape running on an Apple-1 recording and adjust the volume down until the LED on the ACI does not light up. Then slowly increase the volume until the LED lights up, and give it maybe one "number" on the dial more for good measure. With a cassette recorder in good shape this should work.

 

But make no mistake - any cassette interface from the 1970s and 1980s had its quirks and some experimenting with settings, tapes, and recorders was required before success was achieved. Nothing from back in these early years of microcomputers was consumer friendly. Do not expect trouble free operation as with modern computers and USB sticks. But these old cassette systems also had the advantage that you would never, ever catch a virus. USB sticks do have that risk. Some come pre-loaded with spyware from the Chinese manufacturer, and when your computer installs the USB driver from the USB stick, your computer is compromized. Same if you ever plug your stick into any public computer or printer  (like those at a library).

 

- Uncle Bernie

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UPDATE WITH GOOD AND BAD NEWS

I figured one problem out. The Briel/Reactive micro has two versions of basic built in: Applesoft Basic and Integer Basic. You can pick which one you want with this jumper (?) that when left on selects Applesoft and when removed selects Integer.

 

  The good news:

My first problem was leaving the jumper on in Applesoft Basic Mode. When I took the jumper off, the computer switched into Integer Basic mode and I was easily able to enter and re-enter Basic while following the instructions verbatim provided in most Apple 1 Basic literature. 

 

   The bad news:

  Reading and writing seems to work fine as well, I re-enter Basic via E2B3R and it pulls up the Basic command line with the prompt >.

   The problem now is that when I type LIST or RUN the machine flashes the @ symbol and nothing happens. I will continue to experiment with it per your advice. If there is anything else I'm doing wrong, please let me know.   

 

 Once again, the assistance from this forum has been very helpful and I apologize for asking so many questions. I am very excited to get started using this computer! 

 

  Have a great day!

   -Kenopsias

 

 

 

 

 

  

 

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