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haiqu

Senior Member

Joined: 30/07/2011
Location: Australia
Posts: 152

Posted: 10:58pm 04 Sep 2011

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Hi guys (and gals?),

So, I've been pretty quiet for a few days. Geoff's announcement of the new features in 2.5D set me into action over here. I've created a serial card, and it's being made right now.

Features:

- Two serial ports with no handshaking, or COM1 alone with handshaking (jumpered).
- UEXT adapter for expansion cards.
- COM1 has phantom +5V power available on pin 4 (DTR pin).

Limitations:

- UEXT serial is 5V TTL level so the add-on must have 5V tolerant pins.
- !SSEL is not implemented in the MMBasic software. I did connect a bus pin to this connection in case that changes.

COM1 is on a standard vertical PCB mounted DE9 male (they're not actually called DB9's, btw) and has no screw terminals. COM2 is on an RJ45 connector, which offers positive locking, and uses the very cheap (eg $2.12) Cisco Router cable. Both ports are wired as Data Terminal Equipment (DTE).

Here's a snapshot of the layout:

Fully assembled and tested: $30.00 including shipping.
Build it yourself: $25.00 including shipping.

Rob

unzip, strip, touch, finger, grep, mount, fsck, more, yes, fsck, fsck, fsck, umount, sleep

Xiongmao

Regular Member

Joined: 25/08/2011
Location: Australia
Posts: 48

Posted: 08:44am 05 Sep 2011

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Will this work on the Hamfield bus expander?

rhamer
Senior Member

Joined: 06/06/2011
Location: Australia
Posts: 174

Posted: 10:03am 05 Sep 2011

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Xiongmao said Will this work on the Hamfield bus expander?

If your refering to the Powered hub then;

Plug and play probably not.
With a custom cable probably.

Either way I would need to see a circuit to confirm.

Regards

Rohan

Rohan Hamer
HAMFIELD Software & Hardware Solutions

Makers of the Maximite Expander.

http://www.hamfield.com.au

sparkey

Senior Member

Joined: 15/06/2011
Location: Australia
Posts: 819

Posted: 11:52am 05 Sep 2011

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i will be aquireing one of these i will try it out when i get one should be asap but prolly up to two weeks see how things pan out regards sparkey...

technicians do it with least resistance

VK6MRG

Guru

Joined: 08/06/2011
Location: Australia
Posts: 347

Posted: 01:20pm 05 Sep 2011

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Xiongmao said Will this work on the Hamfield bus expander?

By looking at the PCB drawing above, it looks like that's a no. But as Rohan has said, you would have to look at a schematic to check.Edited by VK6MRG 2011-09-06

Its easier to ask forgiveness than to seek permission!

............VK6MRG.............VK3MGR............

haiqu

Senior Member

Joined: 30/07/2011
Location: Australia
Posts: 152

Posted: 03:40pm 05 Sep 2011

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Xiongmao said Will this work on the Hamfield bus expander?

I guess Rohan's answer works for me. I haven't looked at his expander, but if the lines are the same as a Maximite rear connector then I can't see a problem.

It should certainly work with the Dontronics Cross expander.

Rob

unzip, strip, touch, finger, grep, mount, fsck, more, yes, fsck, fsck, fsck, umount, sleep

haiqu

Senior Member

Joined: 30/07/2011
Location: Australia
Posts: 152

Posted: 12:34pm 03 Oct 2011

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Just so that everyone knows, this board is officially dead.

Seems I was confused by the pin numbering system on the Maximite bus connector, the PCBs I got back would have needed many mods to work as intended. With Don's new products coming online soon and Rohan's serial card being available, there doesn't seem to be any point in correcting the errors and making another lot.

Rob

unzip, strip, touch, finger, grep, mount, fsck, more, yes, fsck, fsck, fsck, umount, sleep

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