Новодел Compact 256 turbo

[roma]

Что-то не держит преобразователь +12 вольт.
Без ВГ93 все в норме - 12В есть на 40 ножке. Вставляю чит - напряжение падает до +5 вольт.
Монтаж проверил, в чем может быть причина?

Для поднятия напряжения необходимо уменьшить сопротивление резистора, который стоит последовательно с конденсатором, с 1К до 560 Ом.

[Advertiser]

[Shockwav3]

I just finished assembling my Compact 256 Turbo 1.1 PCB and the machine seems to work completely, only issue is that the video output is way too dark. Any ideas what might cause that? Resistors in the video circuit have been placed as note on the silkscreen (maybe replacing the 300Ohm ones with 27Ohm as in the Compact 128 schematic might fix it?), transistors are KT315B


EDIT: Never mind ... found the problem ... soldered the 100Ohm resistor near KP13 (as represented by the silkscreen) instead of a jumper

[Shockwav3]

Has anyone of you attempted to fix the timings of the machine for Scorpion compatibility? Seems to be about right (69888 tacts per INT, 295 lines on Screen, waitstates), just that the "start of paper" is triggered 8 pixels too early.

[Shockwav3]

I've tried implementing the !INT circuit as found in ZS Scorpion 256 Turbo+ machines (!KS and H6 via TM2) sadly that didn't change anything.
Can anyone of you briefly explain the SS, KS, BK and SCR signals to me? I'm currently guessing SS might be the source of the offset. Sadly that part doesn't match up with the Compact 128 schematic, so I'd prefer to understand the signals first before partially reverse engineering the layout.

[Shockwav3]

Seems like I at least figured out how to reproduce the Timing of the machine in UnrealSpeccy
Check even M1
Check 4T Border
(possibly) Check Port FF - likely not implemented, at least HorrorFasTest doesn't detect it
T-States per INT: 69888
T-States per Line: 224
Start of Paper: 12552
Int fq: 50
Int len: 32

[Shockwav3]

Figured out a solution

[Shockwav3]

What port does the printer port use? I've tried to run some demos with Covox support for DD and FB, but they remained silent, except for some considerable interference.

[Alitius]

Shockwav3, Can you make a foto your PCB?
I also finished assembling this version, and I have not video output signal.
The resistor near KP13 soldered. Other parts seems to work correct.

[Shockwav3]

Try removing that resistor and bridgeing it ... previously I had a very, very dark picture, maybe your TV can't tune in?

[Alitius]

Try removing that resistor and bridgeing it ... previously I had a very, very dark picture, maybe your TV can't tune in?

I bridged the resistor, but nothing happend. I began to search problem
I found not soldered contact. Now I have a picture, but it is a bad quality.