SLG3000 Scanline Generator Review and Demo (http://www.youtube.com/watch?v=S3sb__XK0FQ#ws)
He's got a few good videos covering a few bits and bobs ,cga to vga scaler and the like.For me ,xrgbs aren't need now.
The SLG3000 costs 49Euro, but a clever Korean found a way to do the same thing for a few cents ;D
(http://clubimgfile.paran.com/para/bbs/2011/0220/1298212531_Line_eraser_sch.png)
It's only missing the 3 trimmers to adjust the level.
The author of the discovery is Sharksym, and his webpage with photos is here:
http://sharksym.egloos.com/4930096 (http://sharksym.egloos.com/4930096)
AWESOME !
The capacitors on each ic,are they just smoothing/bypass ones?
Has anyone on here tried the DIY scanline generator yet?
Parts arrived today to do the DIY Scanline mod. I knocked it up but I don't have my RGB to VGA scaler yet. So here's a quick screenshot with my Dreamcast outputting VGA (couldn't find the best game to show it off either!)
(http://i399.photobucket.com/albums/pp74/mmmonkey1975/DIY%20SLG/photo1.jpg)
(http://i399.photobucket.com/albums/pp74/mmmonkey1975/DIY%20SLG/photo3.jpg)
(http://i399.photobucket.com/albums/pp74/mmmonkey1975/DIY%20SLG/board.jpg)
Well, that looks pretty great. It bet it would go well with Street Fighter III.
With the scanlines being non-adjustable...what is the theory here? Would they default to something like "max" on an SLG3000? If so, that's perfect since that's where I'd leave it anyway. From the image though they look like they could be a bit thicker for my tastes...
I'll have to get some parts and try this.
Just added the DIY job to a cheap upscaler, I really like it
(http://i399.photobucket.com/albums/pp74/mmmonkey1975/DIY%20SLG/th_P1080080.jpg) (http://s399.photobucket.com/albums/pp74/mmmonkey1975/DIY%20SLG/?action=view¤t=P1080080.jpg) (http://i399.photobucket.com/albums/pp74/mmmonkey1975/DIY%20SLG/th_P1080072.jpg) (http://s399.photobucket.com/albums/pp74/mmmonkey1975/DIY%20SLG/?action=view¤t=P1080072.jpg) (http://i399.photobucket.com/albums/pp74/mmmonkey1975/DIY%20SLG/th_P1080022.jpg) (http://s399.photobucket.com/albums/pp74/mmmonkey1975/DIY%20SLG/?action=view¤t=P1080022.jpg)
Quote from: ニユ-マン on March 22, 2011, 04:50:59 AM
The SLG3000 costs 49Euro, but a clever Korean found a way to do the same thing for a few cents ;D
(http://clubimgfile.paran.com/para/bbs/2011/0220/1298212531_Line_eraser_sch.png)
It's only missing the 3 trimmers to adjust the level.
The author of the discovery is Sharksym, and his webpage with photos is here:
http://sharksym.egloos.com/4930096 (http://sharksym.egloos.com/4930096)
Something i've never asked ,but exactly how are the ICs making the black scan lines .How's it done ?
IC1A changes state with every HSync pulse, so one line is untouched and the next one is blanked (or vice-versa).
The switch (S1) selects if the blanking circuit (IC2) has to erase the even or the odd lines.
When IC2 is active the RGB lines are grounded and you see a black line.
Quote from: SignOfZeta on April 09, 2011, 03:32:15 AM
Would they default to something like "max" on an SLG3000?
Yes
Quote
From the image though they look like they could be a bit thicker for my tastes...
You can't have thicker scanlines with this method, you are already discarding 50% or your image...
Haha, the simple scanline generator is so ingenious :D
Unused inputs on the 7474 should be tied high or low,don't leave them floating.
Quote from: ニユ-マン on May 24, 2011, 02:37:41 AM
IC1A changes state with every HSync pulse, so one line is untouched and the next one is blanked (or vice-versa).
The switch (S1) selects if the blanking circuit (IC2) has to erase the even or the odd lines.
When IC2 is active the RGB lines are grounded and you see a black line.
Quote from: SignOfZeta on April 09, 2011, 03:32:15 AM
Would they default to something like "max" on an SLG3000?
Yes
Quote
From the image though they look like they could be a bit thicker for my tastes...
You can't have thicker scanlines with this method, you are already discarding 50% or your image...
Do you have an idea how the SLG3000 operates then ?
Quote from: ニユ-マン on May 24, 2011, 02:37:41 AM
IC1A changes state with every HSync pulse, so one line is untouched and the next one is blanked (or vice-versa).
The switch (S1) selects if the blanking circuit (IC2) has to erase the even or the odd lines.
When IC2 is active the RGB lines are grounded and you see a black line.
Quote from: SignOfZeta on April 09, 2011, 03:32:15 AM
Would they default to something like "max" on an SLG3000?
Yes
Quote
From the image though they look like they could be a bit thicker for my tastes...
You can't have thicker scanlines with this method, you are already discarding 50% or your image...
Thanks for the explanation and the diagram of how to make it, I appreciate it. I really like the scanlines this produces, and hope to buy an SLG3000 one day as a comparison of the images and to see what the extra options are like on my TV.
Hi, i follow this circuit diagram but don´t work here, only Black Screen :(
PIN #4 is VCC +5V? the 74LS74 datasheet PIN#14 is VCC.
74LS125 don´t need VCC?
The RGB IN PIN#1,2,3 are connected directly to RGB OUT PIN#1,2,3 together with PIN#3,6,8 74LS125?
IF, someone has a more detailed diagram of the circuit please PM.
TNKS ;D
The diagram assumes that you are going to power the chips so hasn't labelled it. So yes, on the 74ls74 you need 14 - VCC and also leg 4, then GND to leg 7. The 74ls125 expects VCC on leg 14, GND on 7 (as well as 2, 5 and 9)
bigsanta has also pointed out that the unused inputs on 74ls74 should be grounded which I haven't tried yet.
Then wiring up the RGB and H and V Sync is just attaching the labelled legs, with the relevant pins on VGA - 1, 2, 3, 13 and 14
Pete
Quote from: hellbelly on June 17, 2011, 07:15:13 AM
The diagram assumes that you are going to power the chips so hasn't labelled it. So yes, on the 74ls74 you need 14 - VCC and also leg 4, then GND to leg 7. The 74ls125 expects VCC on leg 14, GND on 7 (as well as 2, 5 and 9)
bigsanta has also pointed out that the unused inputs on 74ls74 should be grounded which I haven't tried yet.
Then wiring up the RGB and H and V Sync is just attaching the labelled legs, with the relevant pins on VGA - 1, 2, 3, 13 and 14
Pete
Thanks for the help.
I will try this tomorrow and post the results. ;)
Quote from: Telis on June 17, 2011, 07:34:29 AM
Quote from: hellbelly on June 17, 2011, 07:15:13 AM
The diagram assumes that you are going to power the chips so hasn't labelled it. So yes, on the 74ls74 you need 14 - VCC and also leg 4, then GND to leg 7. The 74ls125 expects VCC on leg 14, GND on 7 (as well as 2, 5 and 9)
bigsanta has also pointed out that the unused inputs on 74ls74 should be grounded which I haven't tried yet.
Then wiring up the RGB and H and V Sync is just attaching the labelled legs, with the relevant pins on VGA - 1, 2, 3, 13 and 14
Pete
Thanks for the help.
I will try this tomorrow and post the results. ;)
Hi folks :D
Well. it´s WORKS now ;D Thank you Pete
PS2 using S-video cable and a cheap S-video To Vga converter at 1024x768, this converter can´t handle 640x480 :'(. In my tests this scanline generator offers a good scanlines using 640x480 , 800x600 scanlines don´t work and 1024x768 works but scanlines is not good. I´m wainting my new video converter to test via Component and 640x480 output.
(http://i51.tinypic.com/2e4zytd.jpg)
Now..... how can i control the scanlines intensity??
Thank you folks and pete.
Sorry for my english and my cam. ;)
I don't think it's possible with this circuit.
Only with the slg3000
http://shmups.system11.org/viewtopic.php?f=6&t=33454 (http://shmups.system11.org/viewtopic.php?f=6&t=33454)
Hi, long time I haven't logged on this forum ! I have just wired my cga/vga converter (using chinese cga/ega to vga converter) + slg3000.
I want to try the diagrams showed on this thread, they're very interesting.
Are you sure that scanlines intensity cannot be controlled ? I thought using triple potentiometer (500 ohm, like piher pt10 used on the slg3000) would be ok, putting one after HD74LS125.
I'm not good in electronics, it's just a question :).
Quote from: gojirien on June 21, 2011, 06:41:05 AM
Hi, long time I haven't logged on this forum ! I have just wired my cga/vga converter (using chinese cga/ega to vga converter) + slg3000.
I want to try the diagrams showed on this thread, they're very interesting.
Are you sure that scanlines intensity cannot be controlled ? I thought using triple potentiometer (500 ohm, like piher pt10 used on the slg3000) would be ok, putting one after HD74LS125.
I'm not good in electronics, it's just a question :).
Hi.
I put a single potentiometer "100 ohms" between the switch and it did not work. Adjusting the visibility of the black line at 50% OR reducing its thickness would be fantastic.
Quote from: gojirien on June 21, 2011, 06:41:05 AM
Hi, long time I haven't logged on this forum ! I have just wired my cga/vga converter (using chinese cga/ega to vga converter) + slg3000.
I want to try the diagrams showed on this thread, they're very interesting.
Are you sure that scanlines intensity cannot be controlled ? I thought using triple potentiometer (500 ohm, like piher pt10 used on the slg3000) would be ok, putting one after HD74LS125.
I'm not good in electronics, it's just a question :).
Quote from: ニユ-マン on May 24, 2011, 02:37:41 AM
IC1A changes state with every HSync pulse, so one line is untouched and the next one is blanked (or vice-versa).
The switch (S1) selects if the blanking circuit (IC2) has to erase the even or the odd lines.
When IC2 is active the RGB lines are grounded and you see a black line.
Quote from: SignOfZeta on April 09, 2011, 03:32:15 AM
Would they default to something like "max" on an SLG3000?
Yes
Quote
From the image though they look like they could be a bit thicker for my tastes...
You can't have thicker scanlines with this method, you are already discarding 50% or your image...
Thank you Telis and Bigsanta for answer. I didn't read ニユ-マン's post carefully, sorry.
I'm currently investigating my slg3000, it has a Texas Instruments ship (red circle on picture) which seems to have same function as the HD74LS74 if I'm not wrong. It has 3 more ICs labelled "JATR" (green circles). I'm not sure of the TI IC's reference, I think it is CDHC73MG4. I haven't found datasheet for the 3 more little ICs yet.
(http://img2.uplood.fr/free/5tka_imag0159.jpg)
Quote from: bigsanta on May 31, 2011, 09:04:36 AM
Unused inputs on the 7474 should be tied high or low,don't leave them floating.
I'm not sure, but I think it MUST be done only for CMOS parts, the proposed circuit uses LS parts so it can be facultative...
Anyway I just wanted to point out that in Telis's circuit the outputs of the '74 ( pin 8 & 9) are both connected to GND which I don't think it' a good practice.
Quote from: gojirien on June 21, 2011, 06:41:05 AM
I thought using triple potentiometer (500 ohm, like piher pt10 used on the slg3000) would be ok, putting one after HD74LS125.
It won't work, this circuit is totally digital, it can only do on/off.
To do what you want you'll have to replace the '125 with an analog circuit (for example an op-amp).
Quote from: Telis on June 18, 2011, 04:09:04 AM
800x600 scanlines don´t work and 1024x768 works but scanlines is not good. I´m wainting my new video converter to test via Component and 640x480 output.
I found this table with the timings of the VGA modes:
Mode Horiz Vertical Horiz Vert Horiz HSYNC Vertical VSYNC
Dots Lines KHz Hz Sync Pol Sync Pol
VGA-480 640 480 31.5 60 3.8 us - 64 us -
VGA-400 640 400 31.5 70 3.8 us - 64 us +
SVGA I 800 600 35.2 56 2.0 us - 57 us -
SVGA II 800 600 37.8 60 3.2 us + 106 us +
SVGA III 800 600 48.0 72 2.4 us + 125 us +
XGA 1024 768 48.5 60 2.0 us - 124 us
As you can see both the SVGA@60 and SVGA@72 modes use positive pulses for the Hsync, maybe that's why it doesn't work.
Quote from: Telis on June 18, 2011, 04:09:04 AM
Quote from: Telis on June 17, 2011, 07:34:29 AM
Quote from: hellbelly on June 17, 2011, 07:15:13 AM
The diagram assumes that you are going to power the chips so hasn't labelled it. So yes, on the 74ls74 you need 14 - VCC and also leg 4, then GND to leg 7. The 74ls125 expects VCC on leg 14, GND on 7 (as well as 2, 5 and 9)
bigsanta has also pointed out that the unused inputs on 74ls74 should be grounded which I haven't tried yet.
Then wiring up the RGB and H and V Sync is just attaching the labelled legs, with the relevant pins on VGA - 1, 2, 3, 13 and 14
Pete
Thanks for the help.
I will try this tomorrow and post the results. ;)
Hi folks :D
Well. it´s WORKS now ;D Thank you Pete
Can i upload a more detailed circuit diagram? Here...
(http://i54.tinypic.com/23rkcc4.png)
PS2 using S-video cable and a cheap S-video To Vga converter at 1024x768, this converter can´t handle 640x480 :'(. In my tests this scanline generator offers a good scanlines using 640x480 , 800x600 scanlines don´t work and 1024x768 works but scanlines is not good. I´m wainting my new video converter to test via Component and 640x480 output.
(http://i51.tinypic.com/2e4zytd.jpg)
Now..... how can i control the scanlines intensity??
Thank you folks and pete.
Sorry for my english and my cam. ;)
Pins 8 and 9 of the 7474 are outputs,so leave them unconnected.
Quote from: ニユ-マン on June 22, 2011, 08:55:42 AM
Quote from: bigsanta on May 31, 2011, 09:04:36 AM
Unused inputs on the 7474 should be tied high or low,don't leave them floating.
I'm not sure, but I think it MUST be done only for CMOS parts, the proposed circuit uses LS parts so it can be facultative...
Anyway I just wanted to point out that in Telis's circuit the outputs of the '74 ( pin 8 & 9) are both connected to GND which I don't think it' a good practice.
Quote from: gojirien on June 21, 2011, 06:41:05 AM
I thought using triple potentiometer (500 ohm, like piher pt10 used on the slg3000) would be ok, putting one after HD74LS125.
It won't work, this circuit is totally digital, it can only do on/off.
Using a hc version of the 7474 ,i've always been told to tie unused inputs,so just assumed the same for LS versions.
To do what you want you'll have to replace the '125 with an analog circuit (for example an op-amp).
Quote from: Telis on June 18, 2011, 04:09:04 AM
800x600 scanlines don´t work and 1024x768 works but scanlines is not good. I´m wainting my new video converter to test via Component and 640x480 output.
I found this table with the timings of the VGA modes:
Mode Horiz Vertical Horiz Vert Horiz HSYNC Vertical VSYNC
Dots Lines KHz Hz Sync Pol Sync Pol
VGA-480 640 480 31.5 60 3.8 us - 64 us -
VGA-400 640 400 31.5 70 3.8 us - 64 us +
SVGA I 800 600 35.2 56 2.0 us - 57 us -
SVGA II 800 600 37.8 60 3.2 us + 106 us +
SVGA III 800 600 48.0 72 2.4 us + 125 us +
XGA 1024 768 48.5 60 2.0 us - 124 us
As you can see both the SVGA@60 and SVGA@72 modes use positive pulses for the Hsync, maybe that's why it doesn't work.
I've always been told to tie unused inputs ,never leave them floating .
Hi folks.
Thanks for the information, i will remove the PIN´s #8 and #9 from ground and update the diagram.
Hey this table you posted is very interesting.
Here more samples from true VGA output
VGA 640x480 (original)
(http://i52.tinypic.com/16ans7c.jpg)
VGA 640x480 (scanlines)
(http://i53.tinypic.com/2yxkmkg.jpg)
VGA 800x600 (scanlines) decrease the screen brightness by 50% and does not generate the scanlines, the screen is very dark.
(http://i55.tinypic.com/2zyxwjr.jpg)
VGA 1024x768 (scanlines) When put this mode you hardly notice the scanlines, I'm starting to like this resolution. The picture becomes softer, the first time i was tested at 1024x768 was on 19" LCD monitor, now i did the test on my TV 32" LCD 1024x768 and looks great, I changed my opinion.
(http://i51.tinypic.com/2jerdpf.jpg)
UPDATED DIAGRAM:
(http://i56.tinypic.com/vhg3uf.png)
One more thing.
I'm using a 74hc74n and a 74ls125n and i have no 5Vcc power supply connected to the chips power pin (14) or pin 4 of the 7474 ,but it is powered just from the vga cable's output ,same with the chip's Vss/gnd pins and all other Vss/gnd connections.Both chips are getting power that is well below what their data sheets recommend .And the finished circuit is now installed inside of a 2 port vga switcher.
Try it on a solderless breadboard (with everything wired as in my wiring diagram ,but without connecting power to the Vcc pins )and check the voltage being received ,well below 4 volts.(also with all unused inputs on the 74hc74 left unconnected)
(http://nfggames.com/forum2/index.php?action=dlattach;topic=4422.0;attach=1272)
Interesting, mine HD74LS74AP does not work without the 5v power ::)
QuoteI haven't found datasheet for the 3 more little ICs yet.
"JATR" is not the IC Part Description/Number, it is only the SMD Code. The SLG-3000 (with adjustable scanline intensity) works difference compare the self-build Scanline Generator. I will make a 1:1 SLG-3000 clone next weekend (for my self-use, mostly for other applications). Unfortunately, I cannot offer a circuit diagramm for the SLG-3000 without permission from the original designer.
Greetings Markus
Moosmann,
Can you tell if the problems in the 800x600 mode are caused by the inversed sync polarity?
Also do you think a circuit like this would work for variable intensity scanlines:
(Switch enable signal from '74) | | +-------/ -----+ <-- Analog bilateral switch with enable input as the 74LVc1G66 | | | | IN --+-/\/\/\/\---+--- OUT <-- Potentiometer | ^ | | +-------+
|
74LVc1G66 Datasheet > http://www.nxp.com/documents/data_sheet/74LVC1G66.pdf (http://www.nxp.com/documents/data_sheet/74LVC1G66.pdf)
QuoteCan you tell if the problems in the 800x600 mode are caused by the inversed sync polarity?
I can tell you this in the next 1-2 Weeks.
QuotelAlso do you think a circuit like this would work for variable intensity scanlines
You answer your own question;)
Greetings Markus
Hi, Just made the scanline circuit with 74LS74 and 74LS125. I have made the same mod that Bigsanta, with a cga/ega/vga converter.
Scanlines work perfectly, but I have a background "grid" on the screen, it's tight but I don't like it, and I don't have this grid with slg3000.
If someone knows a solution (grounding problem maybe ?).
Quote from: gojirien on July 01, 2011, 11:01:09 PM
Hi, Just made the scanline circuit with 74LS74 and 74LS125. I have made the same mod that Bigsanta, with a cga/ega/vga converter.
Scanlines work perfectly, but I have a background "grid" on the screen, it's tight but I don't like it, and I don't have this grid with slg3000.
If someone knows a solution (grounding problem maybe ?).
Hi. This happens at any Resolution? Can you post a picture using this DIY Scanline and SLG3000 for comparison?
Thanks
Hi, I have the background with 640*480, scanlines circuit doesn't work at any other resolution.
Here is the background grid with scanlines circuit :
(http://img2.uplood.fr/free/xwbt_dsc04307.jpg)
And on that picture, use of the slg3000, screen is fine black, no background :
(http://img2.uplood.fr/free/czq0_dsc04308.jpg)
Also, ingame comparison :
Scanlines circuit :
(http://img2.uplood.fr/free/lvt4_dsc04310.jpg)
Slg3000 :
(http://img2.uplood.fr/free/e1h8_dsc04309.jpg)
With the scanlines circuit we can see vertical lines on the picture.
I do not see vertical lines, but image is similar to images with interference.
You've checked all the wires are OK?
All wires are ok, I'm wondering about chips quality, or if I have damaged them during soldering. I'll try next with sockets for the 74 chips.
Take a look on the follonwing picture, on the bottom left you can see vertical lines :
(http://img2.uplood.fr/free/cq81_dsc04310.jpg)
Which scaler are you using, the 2 VGA or one VGA model? I ask as my 2VGA model puts horizontal lines on the image with this scanline mod when using the VGA out that's close to the edge of the board, but it fine when using the middle vga out. (I haven't investigated this further yet, it might just be the placement of the scanline board when I stuck it on the underside of the scalers board)
Pete
JATR
JA = some type of high speed diode
T= where it's made ? malaysia
R=?
From the smd codebook
http://www.marsport.org.uk/smd/mainframe.htm (http://www.marsport.org.uk/smd/mainframe.htm)
CODE DEVICE NAME
JA BAV74 dual sw diodes
JA BAV74 dual diode cc 50V 0.1A
Obviously it can't be either of those ,as they're 3 pin ICs,but these JATR coded smd ICs on the slg3000 ,i think there were originally 6 pins ,but have had the middle pin snapped off (look closely at them, using a jewelers magnifier or something similar ) and you can see the remains of what looks like a leg .
Quote from: ニユ-マン on June 25, 2011, 09:08:15 PM
Moosmann,
Can you tell if the problems in the 800x600 mode are caused by the inversed sync polarity?
Also do you think a circuit like this would work for variable intensity scanlines:
(Switch enable signal from '74) | | +-------/ -----+ <-- Analog bilateral switch with enable input as the 74LVc1G66 | | | | IN --+-/\/\/\/\---+--- OUT <-- Potentiometer | ^ | | +-------+
|
74LVc1G66 Datasheet > http://www.nxp.com/documents/data_sheet/74LVC1G66.pdf (http://www.nxp.com/documents/data_sheet/74LVC1G66.pdf)
That's what those 3 smd JATR coded ICs are ,aren't they :D as they seem to be pin for pin connected on the slg3000 pcb
Quote from: gojirien on June 21, 2011, 05:48:36 PM
Thank you Telis and Bigsanta for answer. I didn't read ニユ-マン's post carefully, sorry.
I'm currently investigating my slg3000, it has a Texas Instruments ship (red circle on picture) which seems to have same function as the HD74LS74 if I'm not wrong. It has 3 more ICs labelled "JATR" (green circles). I'm not sure of the TI IC's reference, I think it is CDHC73MG4. I haven't found datasheet for the 3 more little ICs yet.
(http://img2.uplood.fr/free/5tka_imag0159.jpg)
CD74HC73
The 7473 is just a positive edge dual D type flip flop , where as the slg3000 flip flop seems to be a dual JK negative triggered one .I think only 1 flip flop is being used .But if the slg3000 is using an analog switch which needs E to be active when high and thus Y and Z = on state ,then how come are Y and Z being read as a closed switch instead of open/off ,when the slg3000 is not connected to anything ?
Quote from: bigsanta on July 09, 2011, 12:55:07 PM
Quote from: gojirien on June 21, 2011, 05:48:36 PM
Thank you Telis and Bigsanta for answer. I didn't read ニユ-マン's post carefully, sorry.
I'm currently investigating my slg3000, it has a Texas Instruments ship (red circle on picture) which seems to have same function as the HD74LS74 if I'm not wrong. It has 3 more ICs labelled "JATR" (green circles). I'm not sure of the TI IC's reference, I think it is CDHC73MG4. I haven't found datasheet for the 3 more little ICs yet.
(http://img2.uplood.fr/free/5tka_imag0159.jpg)
CD74HC73
The 7474 is just a positive edge dual D type flip flop , where as the slg3000 flip flop seems to be a dual JK negative triggered one .I think only 1 flip flop is being used .But if the slg3000 is using an analog switch which needs E to be active when high and thus Y and Z = on state ,then how come are Y and Z being read as a closed switch instead of open/off ,when the slg3000 is not connected to anything ?
Because the 74LVC1G66 is an active high switch ,so the 3 in the slg3000 must be an active low version,using something like the 384 version (74LVC1G384)of the same family . ::) ;D
Quote from: hellbelly on July 06, 2011, 02:03:25 AM
Which scaler are you using, the 2 VGA or one VGA model? I ask as my 2VGA model puts horizontal lines on the image with this scanline mod when using the VGA out that's close to the edge of the board, but it fine when using the middle vga out. (I haven't investigated this further yet, it might just be the placement of the scanline board when I stuck it on the underside of the scalers board)
Pete
I'm using the 2 vga one, I've tried the 2 outputs and each make same result for scanlines, so the problem might be with the scanlines circuit. I have to build another one, with sockets for 74's ICs.
Bigsanta, thanks for all info, very interesting.
Another little thing, two days ago I put a LM1881N (usually I'm used to stick it under the cga vga scaler) directly in the scart socket.
(http://img2.uplood.fr/free/dpch_dsc04314.jpg)
Quote from: ニユ-マン on May 24, 2011, 02:37:41 AM
IC1A changes state with every HSync pulse, so one line is untouched and the next one is blanked (or vice-versa).
The switch (S1) selects if the blanking circuit (IC2) has to erase the even or the odd lines.
When IC2 is active the RGB lines are grounded and you see a black line.
Well, instead of tying the (active low)buffer's 3 inputs to ground ,why can't a pot be on those lines instead,allowing us to control the VGA's RGB levels peak to peak voltage (black =0/Vss -0.7 Vcc = full intensity)
I'm not sure if I understand what you want to do with that. Please post a schematic of your suggested modification.
Example
(http://nfggames.com/forum2/index.php?action=dlattach;topic=4422.0;attach=1291)
I don't think it will work, unless you change the 74*125 with an analog switch.
From Wikipedia:
A TTL input signal is defined as "low" when between 0 V and 0.8 V
And even if you use a suitable device, the circuit (as it is) will not work as you wish:
The video signals always go through the 3xPOT, but you want this to happen only when needed.
Oops ,made a few mistakes with that first eagle.sch
Maybe use something like a 4016 ,to replace the quad buffer.
(http://nfggames.com/forum2/index.php?action=dlattach;topic=4422.0;attach=1297)
TTL parts wont work, CMOS (or 74HC) parts may work, but the signal will probably need to be amplified.
Best solution (apart from copying the SLG3000) would be to use dedicated parts, like this video switch:
http://www.maxim-ic.com/datasheet/index.mvp/id/5872 (http://www.maxim-ic.com/datasheet/index.mvp/id/5872)
or maybe this:
http://www.maxim-ic.com/datasheet/index.mvp/id/6469/t/al (http://www.maxim-ic.com/datasheet/index.mvp/id/6469/t/al)
Here's a 90% complete eagle.sch of the slg3000.It's missing the terminal block for connecting a spst switch and enabling the slg3000 to work in vga pass through mode.The Vcc and Vss points for connecting an external psu.Also missing are the two capacitors ,(the 47 uf@25v and the 0805 size 100 nf smdc cap that seem to be there for filtering, when the external psu is used,along with another 0805 size smd 10k ohm resistor(pull up ) (labled as 1002).Also the reset pin on the SO 74HC73m flip flop ,it is actually connected to on of the pins of the terminal block that's there for connecting a spst switch.It then goes to the 10K ohm pull up resistor that's next to the LED's 220 ohm resistor(2200 ) ,the other pin goes to Vss/gnd(,enabling a low input to be sent to the 7473's reset pin ,from a connected spst switch.
Also, the bi lateral switches IC2,3,4 ,these are still not a certainty to be the correct types as in my schematic,they could be active low enabled (or something completely different ),so don't take it as gospel .The pots are 500 ohm each(those in the schematic i've used a 3/triple gang pot instead of the single pots that are on the pcb).The 7473 used in the schematic/slg3000 is infact an m version,not a D(this was down to eagle's library missing the 74hc73m version)
Switch 1 is numbered incorrectly .On the slg 1=switch 4 and 2 =switch 5.(on the latest version of the slg).
All smd resistors ,the LED and all but 1 of the capacitors are size 0805
(http://nfggames.com/forum2/index.php?action=dlattach;topic=4422.0;attach=1315)
Oh, very interesting Bigsanta !
So for my problem with my diy scanlines circuit, I think I know the origin of the problem : I didn't understand that 74LS74 and 74LS125 needed capacitors...Stupid I am^^. Will try with the capacitors, anyone could tell me their value, and the pins locations on Ics where to solder them ?
I used these cmos ICs to make a working diy adjustable slg ,but i think the rgb levels go a bit too dark when the scanlines are set to fully on,but i had been messing with my contrast levels earlier in the week ,so i'll let someone else tell me, if they make one.R4 isn't needed,just tie the reset pin to Vcc instead.
I used much smaller pots (not value) and the dip switches ,i changed them to a side/right angle type of dip switch.Maybe you could remove the analog pots and substitute 3 digital ones like the x9c1025's and operate them with just two switches ,one on the inc and up/down pins (all inc tied together and all up/down tied together and pulled high )?As in my unfinished schematic below?
IC'5 pins's are numbered wrong.IC5C should be numbered as follows;
IC5C (c=1 a=2 b=13 )
IC5B (c=3 a=4 b=5 )
IC5A (c=9 a=8 b=6)
I removed the remaining R1 and R2 resistors and it fixed the problem of getting too dark. There's no need for any resistors ,just remove them all from the adjustable diy scan line maker.
(http://nfggames.com/forum2/index.php?action=dlattach;topic=4422.0;attach=1336)
(http://nfggames.com/forum2/index.php?action=dlattach;topic=4422.0;attach=1344)
How would you double the horizontal lines from an s-video connection and convert it to VGA, in order to use a scan line generator like this? What device(s) would you guys recommend? Thanks,
Matt