Building the KLyball 610

[Jeff]

R10 RX Clock
Remove floppy-disk cable (J3).
Connect a jumper from pin 9 of J3 to pin 10 of J3.
Input of scope to pin 5 of U70.
Adjust R10 for a positive pulse width of 1uSec.

R10 Adjustment.jpg (93.26 KiB) Viewed 20684 times

R19 RX Data
Remove floppy-disk cable (J3).
Connect a jumper from pin 9 of J3 to pin 11 of J3.
Input of scope to pin 4 of U70.
Adjust R19 for a negative pulse width of 6uSec.

R19 Adjustment.jpg (124.44 KiB) Viewed 20684 times

Special Build Note:
I had to change R20 to 10K ohms in order to get R19 to set the correct pulse width.

[MK14HAK]

Using 8" Drives:
TxCLK= 250KHz
TXCLK=260ns +- 25ns
TXDATA=260ns
RXCLK=1uS
RXDATA=2.75uS R20=4K7

[Jeff]

For the last week or so, I have been trying to get a floppy drive working with the 610. As it turns out, (after MANY hours of testing and hair-pulling) I discovered that I made a mistake when building it. The symptoms were that the 6821 was just not doing anything! No input, no output, nothing. I finally traced it to a LOW state on the /RESET pin of the 6821. The 6821 was being held in a perpetual state of RESET. R42 is supposed to pull the pin high after the system boots, but I had soldered one of its legs into the wrong hole on the board, and so it wasn't connected to +5V.

So, anyone building one, should be aware of this potential "gotcha!"

610 R42 Placement.jpg (166.65 KiB) Viewed 20653 times

/Jeff

[BillO]

Not having much time to work on this is leaving me a little frustrated. While I was at least able to read and write to disks using my old 600B board, the new 600D can read, but is only writing a string $24 all over the disk (except track0) during initialization (or anything else). I can read them, but not write. So more debugging...

...Sigh!

[Jeff]

I have completed building the Klyball 610.

Here is a hires photo:
http://www.jeffferguson.ca/osi/610/CompleteWith24K.jpg

And here is a photo of an original OSI-built 610, Rev B:
http://www.jeffferguson.ca/osi/610/OSI_610_revB.jpg

(Dave, you might want to post this to your Hardware archive, as there isn't a photo of a 610 board in there)

/Jeff

[Klyball]

Can some one check there 610 board if there is a connection between pin 9 of U10 and pin 1 of U11,
my 610 is missing the trace so the replica is also missing this trace.

OSI_610-7.jpg (70.21 KiB) Viewed 20397 times

Thanks

[BillO]

Can some one check there 610 board if there is a connection between pin 9 of U10 and pin 1 of U11,
my 610 is missing the trace so the replica is also missing this trace.

Thanks

Hi Grant, did you ever resolve this? What happens if you connect pin 9 of U10 and pin 1 of U11?

[Klyball]

Making the connection give the desired results, if your using hexdos for RTC you need the 1 sec pulse .

Just wondering if anyone one with a real 610 has this connection in copper, its not on my original 610, but it looks to be a later production run as it has solder mask on the back

[Jeff]

http://www.jeffferguson.ca/osi/610/CompleteWith24K.jpg
http://www.jeffferguson.ca/osi/610/OSI_610_revB.jpg

Links Restored

[Jeff]

Bumping this topic for Walter who is currently building one.

/Jeff