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isochronic
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Joined: 21/01/2012
Location: Australia
Posts: 689

Posted: 07:48pm 14 Jun 2017

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Just a thought... there is a USB LCD module at Jaycar - ie a plugin,
presumably there is software supplied/available. Don't know details though.

Grogster

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Joined: 31/12/2012
Location: New Zealand
Posts: 9303

Posted: 04:12am 15 Jun 2017

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led-bloon said Grogs
The SPI Header at the top of the board is pretty much wasted
as it has no CS output.[/Quote]

Dammit!!!

That's another one I missed.
Will fix along the lines you suggest.

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

led-bloon

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Joined: 21/12/2014
Location: Australia
Posts: 205

Posted: 12:09pm 15 Jun 2017

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Take 2:

Actually I wouldn't worry about it.
The COM2 TxD pin can be used in situ as the CS, and anyway, the top
SPI port is more likely to be used when the SSD1963 display is in
use - meaning you could need multiple CS pins and would have to grab
from I2C/PWM/COM2 anyway.
Your call though.

Edit: To use the SPI port off board a CS is necessaryEdited by led-bloon 2017-06-16

Miss you George

Grogster

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Posted: 02:55pm 15 Jun 2017

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I'd never worked with the PI GPIO port before, but ASSUMED they were all IO pins, but lots of them are ground, some are power, and a couple you can't touch at all such as the ID EEPROM pins. That leaves you with only a handful of IO pins to play with, really.

Yes, I agree. I think the best bet would be to use something such as COM2 as your CS line or lines, allowing for an extra two devices on the SPI bus if you did it that way.

So, we're back to the way it sits now, with the exception of me needing to fix the SPI LCD CS line, yes?

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

led-bloon

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Joined: 21/12/2014
Location: Australia
Posts: 205

Posted: 04:27pm 15 Jun 2017

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Yes Sir
My suggestion would be either RS/RD/WR of the SSD1963 as dual purpose.
Any one of these.
The data pins for the SSD1963 display are nicely aligned in a row
on the header and easy to get at as spare GPIOs if required.

Miss you George

bigmik

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Joined: 20/06/2011
Location: Australia
Posts: 2914

Posted: 03:28pm 16 Jun 2017

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GDAY All,

Grogster said Obviously you Aussies have a hard time with stacking stuff up - we kiwi's are much better at stacking then you guys seem to feel comfortable with...

@Grogs,

I don't know what you are talking about.. Here I am taking my family on holidays..

Seriously, That is fine.. I was just pointing out that is would make for a largish stack, If you are fine with that then so am I.. I also have a Pi ZERO -W sitting here waiting for a task and your board may just be what it needs.. I also agree that those plug in Pi displays make no allowance to access the GPIO pins that are not needed for the display modules A real oversight on their behalf.

I have a small HDMI pack-back touch module I hope to play with this weekend if I get time.. but yes the other pins are not accessanble unless you solder wires to the back of the pins .. Silly.

Kind Regards,

Mick

Mick's uMite Stuff can be found >>> HERE (Kindly hosted by Dontronics) <<<

isochronic
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Joined: 21/01/2012
Location: Australia
Posts: 689

Posted: 02:22am 17 Jun 2017

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errh..

Quote ... there is a USB LCD module at Jaycar - ie a plugin

It is at Altronics instead

(with linux drivers) so pin-limited
pi's might plug in, with more software of course

Grogster

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Joined: 31/12/2012
Location: New Zealand
Posts: 9303

Posted: 10:18pm 17 Jun 2017

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@ Mick - I stand corrected. Remind me not to annoy any of your extended family. With so many of them, I would be in for trouble.

@ led-bloon - PCB now uses the RS pin from the SSD LCD for the SPI LCD CS line - pin-13. As you are only using one type of screen or the other, but NOT BOTH, this will do the job nicely I think. At this stage, I think that just using the COM2 header for a couple of CS lines for the external SPI bus I think will do the job OK, but I think I will still make that header a 5-way one, so that the SPI CS line is part of all the lines - keeps it neat and tidy.

EDIT: Oh forget it! Use COM2 for a couple of CS lines for the SPI port if you need them!

Edited by Grogster 2017-06-19

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

lew247

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Joined: 23/12/2015
Location: United Kingdom
Posts: 1702

Posted: 07:33am 18 May 2018

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Hi Grogster
Would you mind confirming or telling me I've got it wrong (again) for the SPI interface?
t_irq 24
t_do 21
t_din 19
t_cs 33
t_clk 23
miso 21
led 13
sck 23
mosi 19
d/c 29
reset 31
cs 33

I'm making a board for my weather display that the Pi will plug into but will be able to use either type of display and will have a HC-12 on it

Grogster

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Location: New Zealand
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Posted: 11:57pm 18 May 2018

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T_IRQ=24
T_DO=21
T_DIN=19
T_CS=26
T_CLK=23
MISO=21
LED SET WITH RESISTOR
SCK=23
MOSI=19
D/C=29
RESET=31
CS=13

I checked this by using the tester tool in Sprint Layout on the actual board, which highlights pads and tracks that are connected when I click on them. This will be a reflection of matherp's original pinout.

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

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