Full VGA resolution (640x480) 3.5" display, composite in

General GBZ-related chat goes here. Share ideas, tips and tricks, or ask questions that don't fit into the hardware/software help forums.
Post Reply
User avatar
Ganreizu
Posts: 552
Joined: Thu May 05, 2016 8:20 am
Has thanked: 168 times
Been thanked: 97 times

Re: Full VGA resolution (640x480) 3.5" display, composite in

Post by Ganreizu » Mon May 23, 2016 3:16 pm

Cannikin wrote:I haven't wired mine up inside the GB shell yet, but the labels on the back of the control board should show you exactly where everything goes. For the composite you want the one labeled CVBS1 on the back (and the GND next to it). 5V to one of the +5V holes and one of the GNDs next to them.
Oh i get it i have to take off all those big white wire posts and use my own wire in all the relevant solder holes. Where do the wires need to go to on the pi0? Wermy's video guide isn't terribly helpful when you have a totally different screen unfortunately. :[
Cannikin wrote:I removed the white plastic connectors completely from mine and that made the board nice and flat (turn it so that the ribbon cable is at the top rather than the bottom). Unfortunately with the cut original GB PCB (the one that contains the power jack, power switch, volume knob and cartridge connector) there wasn't quite enough room between the two boards once the case was assembled to have the HDMI jack lined up with the contrast port. :( I don't see myself hooking this up to a TV though, so I was willing to sacrifice that in order to have all of the rest of the ports stay connected to that cut board.
Ah yeah the HDMI is a huge feature for me especially once we get a controller hub to make multiplayer games easier rather than crowding around a gameboy screen. I tried putting it together as best i could and i think it can still be done. Worst case scenario i'll mod the contrast port window to fit it. I just did a bunch of sanding on the edges to make the screen actually fit, gonna need a screen protector for this thing.

User avatar
codacious
Posts: 30
Joined: Thu May 05, 2016 8:10 am
Location: Texas
Has thanked: 8 times
Been thanked: 3 times

Re: Full VGA resolution (640x480) 3.5" display, composite in

Post by codacious » Mon May 23, 2016 3:59 pm

Ganreizu wrote: Ah yeah the HDMI is a huge feature for me especially once we get a controller hub to make multiplayer games easier rather than crowding around a gameboy screen. I tried putting it together as best i could and i think it can still be done. Worst case scenario i'll mod the contrast port window to fit it. I just did a bunch of sanding on the edges to make the screen actually fit, gonna need a screen protector for this thing.
I'm anxious to see your results. I'd like to be able to keep the HDMI port as well.

User avatar
Cannikin
Posts: 127
Joined: Wed May 11, 2016 3:10 pm
Has thanked: 4 times
Been thanked: 36 times

Re: Full VGA resolution (640x480) 3.5" display, composite in

Post by Cannikin » Mon May 23, 2016 4:16 pm

Ganreizu wrote:Where do the wires need to go to on the pi0?
The only two wires you REALLY need directly from the Pi are the composite ones. Those are here: https://learn.adafruit.com/introducing- ... site-video The square hole on the Pi is the signal, so connect that to CVBS1 on the video board, the round hole next to it is the ground, connect to GND on video board.

You *should* be able to power the screen from one of the 5V headers on the Pi (all of the headers are shown here: http://i.imgur.com/ltd7B84.jpg). To be safe you may want to connect 5V on the screen controller board directly to the PowerBoost to make sure that the ~320mA the screen requires isn't sucking power from the Pi itself.

Here's a discussion (not for the Zero specifically, but should still apply) about how much current you can pull through 5V: https://www.raspberrypi.org/forums/view ... 4&t=105368 Basically whatever the power supply can give, minus the current draw of the Pi itself. So if the PowerBoost can supply 2.0A, and the Pi pulls no more than ~1.6, you should be able to hook up the screen to 5V header. But you're cutting it awfully close!

I'm going to power the screen directly from the PowerBoost and have the 5V headers on the Pi go to my USB hub. I've had a Wifi dongle, keyboard dongle and flash drive all connected to the Pi's USB port at the same time without a problem, so it should be able to handle the power requirements of any accessories I plug into the GBZ.

User avatar
Cannikin
Posts: 127
Joined: Wed May 11, 2016 3:10 pm
Has thanked: 4 times
Been thanked: 36 times

Re: Full VGA resolution (640x480) 3.5" display, composite in

Post by Cannikin » Mon May 23, 2016 4:28 pm

Ganreizu wrote:Ganreizu
Also, the guy in your avatar, Kappa, I used to work with him at a previous job! He used to work at Twitch (I worked with him later) and he put himself into the chat room along with the rest of the devs, but his ended up being the most popular one. That's Josh, he's a good guy: https://twitter.com/lazythunk

User avatar
Ganreizu
Posts: 552
Joined: Thu May 05, 2016 8:20 am
Has thanked: 168 times
Been thanked: 97 times

Re: Full VGA resolution (640x480) 3.5" display, composite in

Post by Ganreizu » Mon May 23, 2016 5:11 pm

Cannikin wrote:answers and stuff
I'm having a difficult time desoldering at the moment and i don't want to overheat the board. :[ Ordered some better tools so i'll give it a try on wednesday.
Cannikin wrote:Also, the guy in your avatar, Kappa, I used to work with him at a previous job! He used to work at Twitch (I worked with him later) and he put himself into the chat room along with the rest of the devs, but his ended up being the most popular one. That's Josh, he's a good guy: https://twitter.com/lazythunk
Ahah that's funny. I just enjoy twitch a fair amount and Kappa in general is hilarious to me

uke
Posts: 41
Joined: Mon May 09, 2016 9:05 am
Has thanked: 2 times
Been thanked: 6 times

Re: Full VGA resolution (640x480) 3.5" display, composite in

Post by uke » Mon May 23, 2016 5:56 pm

Thanks to everyone who bought this screen and is trying to make it work. I'm waiting for mine and this is so useful.

User avatar
Camble
Posts: 882
Joined: Thu May 05, 2016 2:31 am
Location: Scotland
Has thanked: 269 times
Been thanked: 487 times

Re: Full VGA resolution (640x480) 3.5" display, composite in

Post by Camble » Tue May 24, 2016 12:11 pm

Gah! Really wish I'd noticed this before buying my composite screen. These look crisp!

User avatar
Ganreizu
Posts: 552
Joined: Thu May 05, 2016 8:20 am
Has thanked: 168 times
Been thanked: 97 times

Re: Full VGA resolution (640x480) 3.5" display, composite in

Post by Ganreizu » Tue May 24, 2016 5:16 pm

Cannikin wrote:[spoiler="Text"]The only two wires you REALLY need directly from the Pi are the composite ones. Those are here: https://learn.adafruit.com/introducing- ... site-video The square hole on the Pi is the signal, so connect that to CVBS1 on the video board, the round hole next to it is the ground, connect to GND on video board.

You *should* be able to power the screen from one of the 5V headers on the Pi (all of the headers are shown here: http://i.imgur.com/ltd7B84.jpg). To be safe you may want to connect 5V on the screen controller board directly to the PowerBoost to make sure that the ~320mA the screen requires isn't sucking power from the Pi itself.

Here's a discussion (not for the Zero specifically, but should still apply) about how much current you can pull through 5V: https://www.raspberrypi.org/forums/view ... 4&t=105368 Basically whatever the power supply can give, minus the current draw of the Pi itself. So if the PowerBoost can supply 2.0A, and the Pi pulls no more than ~1.6, you should be able to hook up the screen to 5V header. But you're cutting it awfully close!

I'm going to power the screen directly from the PowerBoost and have the 5V headers on the Pi go to my USB hub. I've had a Wifi dongle, keyboard dongle and flash drive all connected to the Pi's USB port at the same time without a problem, so it should be able to handle the power requirements of any accessories I plug into the GBZ.[/spoiler]
So what you're saying here is that if i hook up the screen the the pi0, it might have issues supplying power to all the components but if it's off the powerboost directly it will all be fine? Which pins do i use on the powerboost and pi0 to hook them together? 5V pin on screen board -> 5V pin on powerboost right, then ??? pin on powerboost -> ??? pin on pi0?

Also i realized the ribbon cable for the screen juts out pretty far when the screen is flipped upside down the way we have it. It'll squish up against the power switch on the top half of the case at the very least. Is this something to worry about? I know we have to be fragile with it but it seems we're going to have to at least bend it to fit given that the connector is directly below the cable, and i feel like the power switch will damage it eventually.

User avatar
Cannikin
Posts: 127
Joined: Wed May 11, 2016 3:10 pm
Has thanked: 4 times
Been thanked: 36 times

Re: Full VGA resolution (640x480) 3.5" display, composite in

Post by Cannikin » Tue May 24, 2016 5:33 pm

Ganreizu wrote:So what you're saying here is that if i hook up the screen the the pi0, it might have issues supplying power to all the components but if it's off the powerboost directly it will all be fine? Which pins do i use on the powerboost and pi0 to hook them together? 5V pin on screen board -> 5V pin on powerboost right, then ??? pin on powerboost -> ??? pin on pi0?
So there are at least 3 different pins on the PowerBoost that supply 5V: the one marked 5V, the one marked with a + where you can optionally solder in the big USB header, and then below that, the left of the two pins where you can solder in a wire directly. Those all output the same 5V. So I'd have one go to the PP1 pad on the back of the Pi and another go to the +5V on the back of the screen controller (and of course ground wires going from either GND or G or USB (-) pads on the PowerBoost to PP6 on the Pi and GND on the screen controller).

Unless someone one here is confident that you just have one wire from the PowerBoost go to the Pi's PP1 and then a wire from the Pi's 5V GPIO header to the screen.
Ganreizu wrote:Also i realized the ribbon cable for the screen juts out pretty far when the screen is flipped upside down the way we have it. It'll squish up against the power switch on the top half of the case at the very least. Is this something to worry about? I know we have to be fragile with it but it seems we're going to have to at least bend it to fit given that the connector is directly below the cable, and i feel like the power switch will damage it eventually.
Once the ribbon cable was plugged in I folded it back over the control board and can get it pretty flat:

Image

I don't have any problem getting the two halves of the shell together, just make sure the ribbon is lying flat when you press the two halves together and that it's not getting hung up on any of the solder pads sticking out of the cut GB circuit board on the other side. Did you end up cutting yours like mine or were you going to get rid of that and hotglue the parts in place so you have room to line up the HDMI on the Pi with the contrast slot?

User avatar
Ganreizu
Posts: 552
Joined: Thu May 05, 2016 8:20 am
Has thanked: 168 times
Been thanked: 97 times

Re: Full VGA resolution (640x480) 3.5" display, composite in

Post by Ganreizu » Tue May 24, 2016 5:56 pm

Cannikin wrote:So there are at least 3 different pins on the PowerBoost that supply 5V: the one marked 5V, the one marked with a + where you can optionally solder in the big USB header, and then below that, the left of the two pins where you can solder in a wire directly. Those all output the same 5V. So I'd have one go to the PP1 pad on the back of the Pi and another go to the +5V on the back of the screen controller (and of course ground wires going from either GND or G or USB (-) pads on the PowerBoost to PP6 on the Pi and GND on the screen controller).

Unless someone one here is confident that you just have one wire from the PowerBoost go to the Pi's PP1 and then a wire from the Pi's 5V GPIO header to the screen.
Ahh i think i understand what i need to do with this now. Thank you!~

The pads for the USB go like this?

5V___?____?____ Gnd
O ----- O ----- O ----- O
.........5V___Gnd
..........O ------ O

Did i get that right?
Cannikin wrote:Once the ribbon cable was plugged in I folded it back over the control board and can get it pretty flat:

I don't have any problem getting the two halves of the shell together, just make sure the ribbon is lying flat when you press the two halves together and that it's not getting hung up on any of the solder pads sticking out of the cut GB circuit board on the other side. Did you end up cutting yours like mine or were you going to get rid of that and hotglue the parts in place so you have room to line up the HDMI on the Pi with the contrast slot?
Oh so it's just me being way too scared of damaging the ribbon cable then. I didn't think there would be a problem getting the halves together, just about how it would interact with the solder points on the power switch.

My GB circuit board is currently cut exactly like yours but i was thinking of trimming it down along the edges a little more if needed (give more room on the bottom of the cartridge connector to give space for button PCB wires). I think with the way it is i can get the HDMI to fit in the window, i left the white button board connector on the screen board so i can configure the screen away from default but that is immediately in front of the contrast port so it's a little hard to tell if the HDMI will fit. Removing the upwards bracket that holds the power button might help a LITTLE bit but the cartridge board is still between the pi0 and the front case half anyway.

Post Reply

Who is online

Users browsing this forum: No registered users and 1 guest