Video driver thoughts

[PhilC]

Well done Chris, Is there any further testing you'd like us to carry out with the current board? or should we now wait for the next revision?

[exxos]

Well done Chris, Is there any further testing you'd like us to carry out with the current board? or should we now wait for the next revision?

I don't think there is anything much else to try currently...

You could try adding the 75R resistors in series with the RGB lines and the 47pF caps to see if it makes any difference in video quality at all. ( Note that you may well have 33R already in series).

[exxos]

V3 board if anyone wants to get one made.

VIDEO_DACv3.zip

(11.1 KiB) Downloaded 328 times

[kodak80]

v3 boards ordered from OSH Park.

Is there a component list available?

[exxos]

v3 boards ordered from OSH Park.

Is there a component list available?

Code: Select all

Part     Value                Device               Package      Library              Sheet

BLANK                         1,6/0,8              1,6/0,8      wirepad              1
C1       2.2uf                C-EUC0805            C0805        rcl                  1
C2       2.2uf                C-EUC0805            C0805        rcl                  1
C3       50pF                 C-EUC0805            C0805        rcl                  1
C4       50pF                 C-EUC0805            C0805        rcl                  1
C5       50pF                 C-EUC0805            C0805        rcl                  1
C6       2.2uf                C-EUC0805            C0805        rcl                  1
C8       10uf                 C-EUC1206            C1206        rcl                  1
C10      2.2uf                C-EUC0805            C0805        rcl                  1
CN1                           HDR-1X3-MTA-100      MTA-100-3V   con-hdrs40           1
IC1      STV8438CVQFP44_LARGE STV8438CVQFP44_LARGE PQFP44_LARGE Atari_MB_fixed2018v2 1
JP1                           JP2E                 JP2          jumper               1
R1       75                   R-EU_R1206           R1206        rcl                  1
R2       75                   R-EU_R1206           R1206        rcl                  1
R3       75                   R-EU_R1206           R1206        rcl                  1
SHIFTER  SHIFTER              SHIFTER              DIL40        Atari_MB_fixed2018v2 1
STF      SHIFTER              SHIFTER              DIL40        Atari_MB_fixed2018v2 1

v3.png (157.15 KiB) Viewed 9089 times

BTW - I already sent your V2 PCB + chip

[kodak80]

Cool, thank you. I will wait for these to arrive

[exxos]

BTW - 50pF can also be 47pF is the value is hard to find. I've not looked for any of the parts yet...

[kodak80]

The STV8438CV chip does seem to be very hard to find with Google and non-existent on Mouser.

[PaulJ]

The STV8438CV chip does seem to be very hard to find with Google and non-existent on Mouser.

Here ya go Kodak..
https://www.exdwh.com/data/STV8438CV.pdf

[Icky]

V3 board if anyone wants to get one made.

I take it this is just a neater version of the V2.patch board without the large caps.

V2.patch board

IMG_3353.png (750.8 KiB) Viewed 9060 times