Dragon 64 Serial vs. Tandy Deluxe RS232 Pak

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KenH
Posts: 182
Joined: Fri Oct 12, 2012 9:50 am

Dragon 64 Serial vs. Tandy Deluxe RS232 Pak

Post by KenH »

Is the Dragon 64 serial port implementation the same as Tandy's Deluxe RS232 Pak?
Both are based on the 6551 ACIA.
One obvious difference is that on the Dragon the ACIA board is memory mapped to addresses $FF04 - $FF07, and on the CoCo it is mapped to $FF68 - $FF6B.
Are there any additional differences?
Should it be possible to convert software for the Tandy RS232 Pak to the Dragon by simply changing the control register addresses?
Serenarian
Posts: 29
Joined: Thu Oct 25, 2012 1:28 pm

Re: Dragon 64 Serial vs. Tandy Deluxe RS232 Pak

Post by Serenarian »

I haven't seen the spec for the Tandy RS232pac Ken, but one possible snag is that the Dragon64 port isn't fully RS232 compatible. It only has DTR and CTS available at the DIN socket for flow control whereas the Tandy may use the RTS line as well.

I'm not sure what you are planning, but back in the 1980's I had my Dragon hooked up to my PC via a serial link in order to transfer files and share printers. I used Xmodem on the PC and used the info given in Duncan Smeed's "Inside the Dragon" to knock up some MCode routines to use at the Dragon end.

At first, as an experiment just to pipe BASIC listings to my printer on the PC I simply set BAUD rates at both ends then I used the simple expedient of using pokes to redirect the CHAROUT hook at &h167 to point ot SEROUT (BE98) then used LLIST. I seem to recall using the hook at &h3FE to play with CR/LF and end of line sequences too.

Under OS-9 (before I got the DragonPlus board) I used TERM to allow me use the PC as an 80 column terminal to the Dragon using a simple null modem cable link.
tjewell
Posts: 347
Joined: Mon Oct 19, 2009 4:58 pm
Location: Cambridge, England

Re: Dragon 64 Serial vs. Tandy Deluxe RS232 Pak

Post by tjewell »

Hi all - this old thread ties in with something I've been pondering. Is it possible to use the Dragon as a dumb terminal onto (say) a Linux box via the RS232?

As you might have spotted in this thread - viewtopic.php?f=4&t=5449 - Rolo and I have been looking for terminal software for the Dragon and one suggestion was to use the firmware from the Tandy RS232 Pak. Given the fun we had recently with the Orchestra-90 Pak, this sounds like an interesting challenge - although, of course, if anyone does know of any Dragon 64 software that we could use instead, that would be really useful!

This also begs another question - why does the Tandy RS232 Pak exist? I thought the Coco had a serial port already?

Cheers all!
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tormod
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Re: Dragon 64 Serial vs. Tandy Deluxe RS232 Pak

Post by tormod »

(I replied in the other thread already, then found this.) The CoCo does not have an ACIA, so it uses bit-banging which has its disadvantages.
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