MK1 wont't boot without reset switch pressed

yavuzg

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Hi, as the title summarizes my problem, my MK1 PCB won't boot until I manually press the tact button on the PCB.

Is this normal?
 
Nevermind, I found what the problem was...

I traced back the RESET line to the CPU (TMS34010) with the help of the T-Unit schematics (Page 47 of the manual)

https://www.arcade-museum.com/manua...mbat_1_Kit_TUnit_CPU_1643275101B_Feb_1993.pdf

I noticed that the resistor network, RN6 specifically, which was pulling up a few control lines to the CPU (including /RESET line as well), infact has a crack in the middle :)

IMG_2520_zpslpn7sqgv.jpg


When I desoldered it, it just crumbled...

IMG_2521_zps6lsmnjff.jpg


Then I made a guerilla style resistor network out of 4.7K resistors...

IMG_2522_zpsylowbcfe.jpg


Now my MK1 boots automatically when I power it on...
 
nice. I had graphic glitches on my Smash TV cause one of those broke. tracking that down was pretty interesting.
 
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