DonNews #19 26 февраля 2003

Железо

Repair - Continuation of cycle repair the Pentagon. "

__________________________________________


         REPAIR



           No Way Out in TR DOS.

(C) Wild / oHg \ XXL
__________________________________________

If you checked the ROM and the condition that
to him, the cause of this fault
may be defective or trigger D76
Controls that trigger. For
checking, click RES, and make sure
that appeared normal on the screen menu.
Then check whether the trigger D76
in a single state. Execute
RANDOMIZE USR 15616 and make sure that
trigger D76 moved to the zero state.
If not, then (without the Z80 and
ROM) to submit a high potential for stem
D13 / 1, 2, 37, 39, 40 and a low potential for
foot chip D13 / 4,5,19,27,38. Then
Set signal ROM2 to 1, writing in
Register D62/12 unit in the fifth grade (ie
signal C36 = 1). Under these conditions, the zero
potential to appear on the derivation
D77 / 6, D77 \ 3, D77/11. This leads to
Installation trigger D76 in the zero state
ie, D76 / 9 = 0. In this case, you're on the waters of the chip 
D82 / 4, D82/582/6 will be high potential. Then press the RES-a

will lead to a low potential for
element D82 / 4, and hence on the D82 / 6 iD76/10
ie the flip-flop D76 goes into the unit
state. At the same time and the signal ROM2
will is -0 due to the fact that C36 = 0 (
RES D62 zeroed). If so, and
element D76 is not translated to 0 on the team
transition in the TR DOS, then pick up the capacity of C3.
You can also install the C = 300 pF and
R = 2K between the D76/10 and +5 V.