[Coco] CoCo 1 troubles

Salvador Garcia salvadorgarciav at yahoo.com
Tue Dec 22 11:35:20 EST 2020

 Thanks Art and Curtis!

My intention is to upgrade to a 6309, taking advantage that the uProcessor is socketed.

Currently, that is easier said than done. I have a spare 6309; however, right now I am vacationing at my other home in Mexico. I moved all my PC gear here when we (Mom. Dad, sister, and I) moved to Mexico back in the 80s. All my CoCo stuff is here, with exception of the new stuff that I have bought recently (last few years).

This means that I will have to wait to my next visit to upgrade to the 6309, as well as swap keyboards.

Additionally, I recall that the IO error could be something trivial. I don't have a cable replacement (here or in the US), so I can't immediately swap that out, but I have plenty of time to purchase one in the coming months.

I would like to go back to basic* and verify that, to begin with, I have the flat cable connected correctly. The cable has a line of a different color which indicates pin 1. (It is usually red, but here is it a dark gray).This line is to the right of the cartridge. Said another way, when the cartridge is plugged in, the different colored line is towards the rear of the CoCo. I am assuming this is "pin" 1.

The different colored line is at the the top of the floppy drive's connector. This is a vertical unit, so in this case, pin 1 is at the top. I assume this is the correct way to connect the cable.
A behavior I noticed is that when the CoCo attempts to access the floppy drive (when using dskini0 or Dir) there is visible RF interference on the flat panel TV that I am using. Aside from the fact that the CoCo's screen looks terrible, the interference is noticeable when the drive is accessed.

As an additional note, right now I am using an RF to RCA adaptor to connect the CoCo's video out tot he TV's RF in. Another plan is to get better video on this unit, but first things first :-)

Thanks! Salvador

* I haven't decided whether I meant this as a pun or not.     On Tuesday, December 22, 2020, 12:55:38 AM CST, L. Curtis Boyle <curtisboyle at sasktel.net> wrote:  
 I have had that HALT problem too, and it was the CPU. At this time , you could replace it with a 6809 or 6309. 

Sent from my iPhone

> On Dec 21, 2020, at 11:23 PM, Arthur Flexser <flexser at fiu.edu> wrote:
> The inability to format a disk also suggests a possible 6809 problem,
> specifically with the HALT line.  For $6 or $8 bucks or so, you could order
> a new 6809E.  Worth the gamble, in my opinion, assuming you cannot borrow
> one from another computer or elsewhere.  (This is assuming the disk drive
> works correctly for functions other than formatting.)  If the HALT line is
> not working right, you should also see trouble when you try to read or save
> a very long file, or try to boot up OS9..
> Art


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