Vic 20 user port at no more than 1200 baud?

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rwv01
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Vic 20 user port at no more than 1200 baud?

Postby rwv01 » Thu Oct 19, 2017 12:51 am

Hi guys.
For some reason, I my Vic is only able to operate at 1200 baud or less
with my modem or RS232 interface. The modem is an Aprotek Minimodem C24 and the RS232
interface is a Vic 1011A, both capable of 2400 baud rates as are the terminal programs used supposed to be.
Any ideas about this?

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Mike
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Re: Vic 20 user port at no more than 1200 baud?

Postby Mike » Thu Oct 19, 2017 4:23 am

The RS232 routines of the VIC-20 KERNAL don't work reliably with more than 1200 baud, and also have their share with other bugs (for example, the hardware handshake is broken). However, lately, srowe developed a wedge which fixes the errors of the original code, and which should also work at 2400 baud - see here for more details.

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plbyrd
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Re: Vic 20 user port at no more than 1200 baud?

Postby plbyrd » Thu Oct 19, 2017 5:02 am

NinjaTerm supports 2400 baud. I've used it reliably with the EZ232 interface and a RPi. I had mixed results with the Jim Drew WiFi modem.

https://github.com/sharpninja/ninjaterm

rwv01
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Re: Vic 20 user port at no more than 1200 baud?

Postby rwv01 » Sun Oct 22, 2017 5:05 pm

Thanks guys.
I tried srowe's wedge but I could only get up to 1200 baud, even with ninjaterm.
Of course It could be just my equipment, or maybe I didn't load the wedge properly.
I loaded it first with 32k ram (,8 + run right?), and at the ready promt I loaded the terminal program and ran it.
As I understand from the thread about it, the wedge only supports up to 1200 baud at this point.

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Mike
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Re: Vic 20 user port at no more than 1200 baud?

Postby Mike » Sun Oct 22, 2017 5:17 pm

rwv01 wrote:[...] I loaded it first with 32k ram (,8 + run right?), [...]

Not quite so. You need to load the wedge absolute, with ",8,1" and then start it with SYS40960. Indeed RAM in BLK5 is necessary.

After that, it's also necessary to reinit pointers of BASIC with NEW, so you won't get any ?OUT OF MEMORY errors (<- this is not especially related to the wedge, it happens with all programs/data that are loaded outside the memory range available for BASIC programs).

That being said, it would actually be nice to either prepend a BASIC stub (so the file can easily be loaded and run like a BASIC program) or prepend a cartridge header. Srowe?

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srowe
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Re: Vic 20 user port at no more than 1200 baud?

Postby srowe » Mon Oct 23, 2017 11:53 am

I'll stick an autostart on the front of it.

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srowe
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Re: Vic 20 user port at no more than 1200 baud?

Postby srowe » Mon Oct 23, 2017 12:45 pm

Try the following.
Attachments
rs-232-fix-4.zip
(8.12 KiB) Downloaded 4 times

rwv01
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Re: Vic 20 user port at no more than 1200 baud?

Postby rwv01 » Thu Oct 26, 2017 11:59 pm

Thanks for the update, srowe.
I'll let you know what happens!

rwv01
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Re: Vic 20 user port at no more than 1200 baud?

Postby rwv01 » Sat Oct 28, 2017 11:52 pm

OK. I was able to use the wedge at 2400 baud with Ninjaterm and Plus Term.
I loaded the wedge using ",8,1" and the terminal programs with ",8 +run".

Also tried it with Mighty Term, but could not get it to work. Mighty Term has to be loaded
using ,8,1, then sys8192. Could that be causing a conflict?

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srowe
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Re: Vic 20 user port at no more than 1200 baud?

Postby srowe » Sun Oct 29, 2017 1:54 am

Shouldn't do. As long as Mighty Term doesn't try to change the NMI or OPEN vectors is should work too.
You are doing a reset after loading the wedge, otherwise it won't be functioning.

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RobertBe
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Re: Vic 20 user port at no more than 1200 baud?

Postby RobertBe » Sun Oct 29, 2017 4:59 am

rwv01 wrote:OK. I was able to use the wedge at 2400 baud with Ninjaterm and Plus Term.

Plus Term... sweet!

Writing from the Los Angeles area,
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Fresno Commodore User Group
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