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[Wall_Fodder]

greengiant...can you tell me which distributor? I would like to get a few of those for myself.

[greengiant]

Goto the website for JST, then check under 'Distributer Stock Check'
Then contact any of the companies that show up.

You can call them all up, ask for like 5 samples. You end up with some 30 connectors free

[EmperorPsiblade]

gg:
what are the pros and cons of using this?

[greengiant]

The pro's.... no need to spend $80 on a SPI lcd.
Instead $5-10 on the adapter + $10-20 on a normal parellel lcd.

Cons... none.



Update. I havent posted anything or any news because Iam having a very hard time getting XBMC to work properly with the LCD.
The way the SPI works, the data is only being shifted out every 2 cycles provided by the XEN. Along with that, there is a 1msec delay in the display code that is needed to compensate for this 2 cycle delay. The end result is that XBMC tries to update the LCD every frame which equals about 6-12 commands sent out to the LCD, with the delays and such the LCD only ends up getting 4 of those commands which after about 10 seconds makes the lcd go crazy because the commands get messed up. I have brought down the update to 1 time every second (instead of 30 times/second which is 1 frame) and it still happens but after 60-80 seconds.
Iam working on something, see If i can improve the updates or something so this is better, I have also inquired with Ozx into the SPI library.

Will hope to have something soon.

[antiflag1980]

Count me as a buyer when you get ready to sell your finished product.  Good luck!  Hopefully if you get it working well in xbmc and start selling them it will encourage more programmers/teams to inlude LCD support into their apps, since a larger user base will actually use the feature since it will be much more affordable.  If cable lengths aren't a concern I don't have any idea on how to do it since the xbox controller only has the one extra yellow wire but lcd screen in the xbox controller would be a really sweet mod, you know, like the dreamcast vmu.  Now that I think about it Dreamcast vmus would be an insanely cheap source of LCD screens (like $4 used), too bad I seriously doubt there would be any way to use them, I'm sure they have some proprietary sort of connection besides serial or parralell, although DCs do have a serial port.  Hell some people are electronics gurus, you never know.  I saw some dude on some site somewhere who made use of that serial port to network the DC to a PC.

[greengiant]

Good news and bad... regarding the Connectors for the xenium.

The connectors have no minimum and are considerably cheap.
BUT,
the crimps for the connector, JST #SSH-003T-P0.2
Are sold by the reel, 1 reel is 23K
So that means 1 reel is around $400. I dont want to spend that much.
I will be contacting other distributers to see if they can sell in lower qty.

[greengiant]

Well iam bored now of all this fooling around. It just not working for me.
Iam sure one of you brilliant people out there can solve the timing issue.
So here is what i got so far...I will include all the info on how and such. Parts, etc.
Source code too. I expect you know how to connect a parallel LCD already to a device that can use it.

Check it out at Parallel LCD on Xenium

Ill be updating it and posting schematic picture, as well as build pictures as I update it more.

[antiflag1980]

That sucks, I was looking forward to your finished project.

[greengiant]

I was able to do it.. and iam now going into production.
testing prototypes and such at the moment.

I was unable to do it with the HC chip, so I moved over to a PIC soltuon. Much better and allows plug-and-play of the adapter, and possible future expansion for whatever.

Check the thread labeled, "Spi2Par LCD"
or the website http://cheaplpc.com/xenlcd

[Master-Chief]

[antiflag1980]

Me too, glad to hear you got it working.

[greengiant]

Well, I decided to go back to the original HC design to see if I could get that working. Im not gonna give up, even if the Spi2par is much more sophisticated and fully plug-and-play...so...

Over the past day or so, I had been thinking of what could possibly fix the timing issue that was happening with the original HC version. Well I sort of knew long time ago, but wasnt sure on how to fix it. Well A few months back I had gotten some information from Xodus on how to access the SPI port directly (what I mean is how to control the actual Pins directly, avoiding the Software SPI layer).

Well recently I started to think of how to use that to my advantage, and so over the last day I came up with a simple, but good design of connecting the HC IC to the Xenium in such a form that there is NO timing problems.

Backtrack somewhat, the timing problem came from the fact that the HC595 chip is a serial -> parallel shifter IC, but it requires a signal to go High once all the bits have been shifted in. Since you have no means of doing this with the Xenium SPI port inherently as part of the Software SPI port then I left it at that.

But once you have full control over the I/O Pin's you can make the software control anything in whatever way you want. So I went about connecting the HC ic's serial in and clock to the normal SPI0 and CLK lines of the Xenium, and using the Software SPI port to send the data to the shifter, then connected the SPI1 Output line to the HC IC's "put out" line. So that in software I sent the shifter the data via the Software SPI port then manually took high SPI1 Output line and the data would appear on the d0-d7 lines, then bring the SPI1 low again.

This was easy to encapsulate into a function that could then be really easy to integrate into XBMC (simply replace the Outb function with my own).

So the results.... I have left XBMC running now for well over 3 hours, and still not a single glitch.

The only side problem, is that Contrast and Backlight arent software controllable, so you may need to use a POT or resistors to permanently set those. But then again, once you have them set, not likely you will change them again.

The other downside is that you will need to use a Custom build of XBMC. I will try and contact the Dev's once again to see about adding this into the official CVS, but as some of you remeber from the last time (adding contrast for Xenium) it took well over a month to get them to even notice the code. So I dont expect to see these changes in an official build for some time.


I will be posting soon on my website http://spi2par.info under 'HC Ver' (may not exist the link yet) the schematics and information on how to build the thing yourself. All for under $1 !!!!  And works with ANY parallel LCD.

[Master-Chief]

[greengiant]

Ive been busy building XIr's so havent had time to post the info... so ill quickly explain it and mayby get something up in the next week.


You use the HC595 to shift in the serial data from the SPI 0 port into the IC and output it via the 8 data pins.
To tell the HC chip when to put the shifted data out to the 8pins it needs an extra line going from low to high. This is accomplixhed using the SPI1 out port as a regular i/o pin. This off course requires the actual addresses and such for the Xenium and hopefully within a few days I can get permission to release this code.

Then with this basis, you simply have 8 data lines you can control from the xbox.

From here, you use a modified Smartxx/X3 LCD code thats already in XBMC to control the LCD. The only modification is that instead of using the outb routine for the specific modchip, you use a new outb routine.
This new routine, simply, takes in the data and the process is:
send data out the spi0 port (using the xen spi lib)
then, bring high the spi1 out pin, bring it low.
Thats it.

Quite simple really.


Wiring of the HC chip to lcd is exactly as per smartxx diagrams. SPI0 Out connecst to the serial in of the IC, CLK to CLK, and SPI1 out to the shift data out line (cant remvber the actual name right now). Provide power and ground, and your done.