WDI to IDE adaptor (6)

[Mike Arnold]

Aron, when you start looking at the PCB layout could I ask for one small change? Could you add a 22k pullup resistor from J4 pin 3 (DD7 on the IDE bus) to +5V. Let me explain.

I have redeveloped the software to handle two drives on the IDE bus (master & slave) and that all works. However, I really need to be able to detect whether a slave device is installed or not. If there is no slave unit and I try to address it then the bus will float in an indeterminate state. DD7 is the busy bit for a status read so if I find it high then I know that the slave is not installed or faulty.

If it is not possible then I can always solder a resistor on the prototype board.

Thanks

Mike

[Aron Hoekstra]

shouldn't be a problem, 1/4w or can I just go with a tiny 0603 (1/10W) surface mount part?

--
You received this message because you are subscribed to the Google Groups "Cromemco" group.
To unsubscribe from this group and stop receiving emails from it, send an email to cromemco+u...@googlegroups.com.
To view this discussion visit https://groups.google.com/d/msgid/cromemco/c0963772-a087-4abe-b160-e7f2e2d868e1n%40googlegroups.com.

[Peter Higgins]

A 1/10W SMT resistor will be fine.

[Mike Arnold]

I agree with Peter. In fact the dissipation is only 1mW so no problem. 

I am having a few snags with working out what is on the IDE bus as it appears that the master steps in if you address the slave and the master knows it's not there. Anyway, that pullup resistor will allow me to detect if no drives are connected to the bus so worth having.

Hope you had a good holiday.

[Mike Arnold]

A quick update. 

A small group of us are testing out Aron's prototype S100 boards and things are looking good. A few tweaks are required to go from prototype to production but all manageable. I am updating the embedded software to give more functionality and track down a bug.

This has all taken a long time to get to where we are but then again no-one here gets paid so we do what we can when we can.

I have a grainy video of the board working on one of its tests under Cromix Plus if you are interested.  Link -> https://www.dropbox.com/scl/fi/93auo46pqrz1x012eq1yd/MVI_3423.MP4?rlkey=oaycrs6ap4fq8l2swy13zno34&dl=0

Mike

[Mike Stein]

Aww... and you didn't send me one?

J/K ;-)

Remind me, does it work with the WDI, the WDI-II or both?

m

To view this discussion visit https://groups.google.com/d/msgid/cromemco/517e7b6d-9c70-4453-bdcf-91641df80780n%40googlegroups.com.

[Mike Arnold]

Sorry Mike, maybe it got lost in the mail........  :-)

The board works with both WDI and WDI-II. It supports all main Cromemco operating systems (obviously not Unix). 

[Mike Stein]

Well, I guess someone has to actually *buy* one... ;-)

ISTR that it only emulates the 7710 HD11  and not the HD5 or HD20?

BTW, I've got a few WDI-IIs if anybody needs one.

m

To view this discussion visit https://groups.google.com/d/msgid/cromemco/091e3207-cb93-4686-8fa5-91d3bdc4586an%40googlegroups.com.

[Mike Arnold]

Mike, you are right. It emulates four IMI7710s. I did think about the HD5/20 but there are some technical constraints with them because they are so dumb compared to the 7710.

The WDI-II is the more reliable board so I recommend it unless you are running CDOS 2.36 which only works with the original WDI.