65816 Projects

[flashjazzcat]

57 minutes ago, leech said:

Has it been tested with loading through the U1MB?

Yes it works perfectly well, run from SIO devices or directly from the SIDE/SIDE2 HDD. No real reason why it wouldn't (note: MBI is disk based).

58 minutes ago, leech said:

Figured I could put it in there, as currently whenever I try to use BASIC, it just gives me errors.

What kinds of errors?

[leech]

16 minutes ago, flashjazzcat said:

Yes it works perfectly well, run from SIO devices or directly from the SIDE/SIDE2 HDD. No real reason why it wouldn't (note: MBI is disk based).

What kinds of errors?

Oh, I was thinking of flashing it in ROM alongside the Altirra Basic and Rev C.

 

If I set Rapidus to the Rapidus mode it just shows Boot Error.

This is with multiple combinations (this particular one is with Altirra Basic and Altirra OS 3.20.  Figured I probably just need to put the Altirra Basic for the 65816 in one of the slots.

[flashjazzcat]

5 minutes ago, leech said:

Oh, I was thinking of flashing it in ROM alongside the Altirra Basic and Rev C.

Not a hope, unfortunately. But MBI runs almost instantaneously from the HDD on an U1MB/SIDE2 setup.

5 minutes ago, leech said:

If I set Rapidus to the Rapidus mode it just shows Boot Error.

And what storage device are you trying to boot from? Have you configured the PBI HDD on SIDE2? What disk operating system do you propose to use? Try enabling SDX in the front menu.

Edited June 2, 2020 by flashjazzcat

[leech]

12 minutes ago, flashjazzcat said:

Not a hope, unfortunately. But MBI runs almost instantaneously from the HDD on an U1MB/SIDE2 setup.

And what storage device are you trying to boot from? Have you configured the PBI HDD on SIDE2? What disk operating system do you propose to use? Try enabling SDX in the front menu.

Oh, this was just to get BASIC to load.  As soon as I set Rapidus to "Classic" mode it works.  So was just assuming I would need to have a specific version of BASIC for the 65816.  And also assumed I could snag the Altirra version out of the emulator and use uflash to put it into one of the OS slots.  But it sounds like there is the version posted to use

 

Edit: SDX does work fine in Rapidus mode.  It's just BASIC that was giving me a Boot Error. 

Edited June 2, 2020 by leech

[flashjazzcat]

58 minutes ago, leech said:

As soon as I set Rapidus to "Classic" mode it works.

58 minutes ago, leech said:

It's just BASIC that was giving me a Boot Error.

You're not really observing a failure of BASIC to run. You're seeing a boot error message generated by the underlying OS. Rapidus in 'Rapidus' mode may be using the 65C816 OS, but from your description it's hard to nail down exactly what's present and what is not.

 

Enabling SDX simply prevents a disk boot (since DOS is thereby booting directly from ROM), hence no 'Boot error' business.

Edited June 2, 2020 by flashjazzcat

[leech]

17 minutes ago, flashjazzcat said:

You're not really observing a failure of BASIC to run. You're seeing a boot error message generated by the underlying OS. Rapidus in 'Rapidus' mode may be using the 65C816 OS, but from your description it's hard to nail down exactly what's present and what is not.

 

Enabling SDX simply prevents a disk boot (since DOS is thereby booting directly from ROM), hence no 'Boot error' business.

Yeah, SDX runs just fine.  I just get the boot error when attempting to run basic with the Rapidus enabled.  Makes sense if it has a separate OS for it which does not have basic built in.

 

I mostly niticed this when I was testing out pri ting from basic, as I had the Rapidus enabled when I started the process.  Figured I would play around with the different operating systems too, it is also when I found that bug with LPRINT in Altirra Basic.

[flashjazzcat]

Just now, leech said:

I just get the boot error when attempting to run basic with the Rapidus enabled.  Makes sense if it has a separate OS for it which does not have basic built in.

The Rapidus OS should be capable of running the built-in BASIC just fine. BASIC is not part of the OS; it is an internal 8K ROM whose state is managed by bit 1 of PORTB.

 

I get the feeling that when Rapidus is enabled, you have SDX turned off for some reason. If you enable SDX, you should observe basically identical boot and BASIC behaviours in both modes of operation.

 

[leech]

I can start basic from Spartados.  And yeah, I figured the BASIC ROM and OS ROM are separate. 

I just could not boot directly to it.  That is where it is getting the error.  It is the same behavior you would get if you tried to load off a disk that requires basic, but you hold down the option key.

 

This reminds me that I need to finish setting up Spartados X ?  Do wish I could get the 80 column mode of the VBXE to work at the command prompt (probably can, but that is for another thread after I do research!)

[+Stephen]

3 hours ago, leech said:

This reminds me that I need to finish setting up Spartados X ?  Do wish I could get the 80 column mode of the VBXE to work at the command prompt (probably can, but that is for another thread after I do research!)

Ping me if you need some tips for getting this set up.  I have a nicely configured full-time 80 col setup I can share with you.

[leech]

20 minutes ago, Stephen said:

Ping me if you need some tips for getting this set up.  I have a nicely configured full-time 80 col setup I can share with you.

Thanks, ping sent! 

[drac030]

On 5/11/2020 at 3:57 PM, drac030 said:

Namely, the Pokey's RANDOM register $d20a is too slow. Normally one should wait 8 clock cycles between consecutive reads, and with a CPU clocked at 1.77 MHz it is not a problem, but on Rapidus the 8 slow bus cycles are equal to over 90 CPU cycles, so if one does a LDA RANDOM twice in a row, the results may be visibly correlated.

Just for the records, I have found somewhere this routine (I do not know, who is the author):

 

rnd  .zp
fix  .ds 1
seed .ds 1
     .code
     lda fix
     lsr
     rol seed
     bcc ?s
     eor #$b4
?s   sta fix
     eor seed
     rts

When the seed variable is from time to time (e.g. once a VBL) loaded with the contents of $d20a, the results are seemingly as good as using the $d20a reads on stock Atari, and there is no visible dependency on the CPU speed.

 

Edited November 27, 2020 by drac030

[fenrock]

11 minutes ago, drac030 said:

Just for the records, I have found somewhere this routine (I do not know, who is the author):

 

rnd  .zp
fix  .ds 1
seed .ds 1
     .code
     lda fix
     lsr
     rol seed
     bcc ?s
     eor #$b4
?s   sta fix
     eor seed
     rts

When the seed variable is from time to time (e.g. once a VBL) loaded with the contents of $d20a, the results are seemingly as good as using the $d20a reads on stock Atari, and there is no visible dependency on the CPU speed.

 

http://forum.6502.org/viewtopic.php?p=62141&sid=23dba856425b702dba7e4b4be77fa141#p62141

 

This mentions it being the "Batari Basic rand16" function.

 

Edited November 27, 2020 by fenrock

[drac030]

Yes, that is it. I vaguely remembered that it has something to do with Atari 2600. So the author is probably whoever wrote that Batari Basic.