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f1fco

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Joined: 18/03/2012
Location: France
Posts: 155

Posted: 12:14pm 03 Aug 2014

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hello friends of Maximite... (and others)

I have received two PCBs of ASCII video terminal from Silicon Chip
just a little question :
what are the values of resistors on pin RxD ?
on the photo of the card, I see 4.7K and 47K (to pullup to 3.3V)
on schematics, I read 10K and 100 K

on the PCBs from Silicon Chip, the layout of this 2 resistors is painted in black !!!

what is right ?

other problem : I cannot program the PIC32MX250F128B on the PCB with my PICKIT3
(device not found...)
PGD and PGC of PICKIT3 is linked to pin 2 and 3 of the PIC

on the microMite board, PGD and PGC are linked to pin 4 and 5 of the PIC

I try to program the PIC on the board of my microMite and it works !!!
after, I upgrade to version 1.2 via USB on the board of the ASCII terminal
and all is OK

Pierre

73s de F1FCO

WhiteWizzard
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Joined: 05/04/2013
Location: United Kingdom
Posts: 2927

Posted: 12:17pm 03 Aug 2014

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You can use either! As long as you don't mix. I have used a 10K & 100K pairing and also a 4.7K and 47K pairing. I challenged this with Geoff when initially reviewing documents and he has confirmed this too.

WW

WhiteWizzard
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Joined: 05/04/2013
Location: United Kingdom
Posts: 2927

Posted: 12:19pm 03 Aug 2014

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Also, REMOVE BAUD rate links when programing PIC. One of them is shared with an ICSP pin causing it to be grounded! If you are selecting 38400baud via jumpers then this will affect it.

WW

f1fco

Senior Member

Joined: 18/03/2012
Location: France
Posts: 155

Posted: 12:27pm 03 Aug 2014

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thank you WW
my problem was here
the baud jumpers are in place !!!

I can go to bed in peace (it is 00:27 in France)

Pierre

73s de F1FCO

WhiteWizzard
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Joined: 05/04/2013
Location: United Kingdom
Posts: 2927

Posted: 12:30pm 03 Aug 2014

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Only 00:27 - plenty of time to program your PIC and solder in those resistors then!

Grogster

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Joined: 31/12/2012
Location: New Zealand
Posts: 9492

Posted: 01:30pm 03 Aug 2014

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f1fco said thank you WW
my problem was here
the baud jumpers are in place !!!

I can go to bed in peace (it is 00:27 in France)

Pierre

I made that opps when I tried to program my VT100 unit!!!!!

Smoke makes things work. When the smoke gets out, it stops!

f1fco

Senior Member

Joined: 18/03/2012
Location: France
Posts: 155

Posted: 11:46pm 03 Aug 2014

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this monday morning, I solder the resistors, upgrade to version 1.2 and ALL IS OK !

thank you again WW

question on MicroMite.org :
is it the PCB for ASCII terminal available soon ?

Pierre (under the sun in south of France)

73s de F1FCO

Grogster

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Joined: 31/12/2012
Location: New Zealand
Posts: 9492

Posted: 02:30am 04 Aug 2014

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Bonjour.

You can download the PCB pattern as part of the construction kit.

Goto Geoff's page on the VT100 terminal here.

Scroll right down to the bottom.
Under DOWNLOADS, click to download the construction pack - 2nd from the top of the list.

You can find it there, and get some made yourself at the likes of iTead Studio, as they will make you ten boards for only about US$15 + P&P from what I remember - pretty cheap.

I am guessing that there will also be kits available soon from the likes of MicroMite.org and others. You can also buy the blank PCB from Silicon Chip magazine's on-line store if you like.

Smoke makes things work. When the smoke gets out, it stops!

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