Re: A Bad Apple

[noone@nowhere.net]

The issue still sounds like a CPU/socket problem.  Of course it may be a
reset issue.  Unplug the keyboard as well and fire it up.

If you can, verify the clock it spinning and that the reset line is in
it's proper state.  (One state on power up and to the other state about
1/2 second later.)  Pin 40 is reset, I can't tell where the clock signal
is from the diagram I have here. (see below)

Since you have replaced the socket, I'd take as close look at the CPU
socket as possible.  Get a bright light and magnifying glass and have a
look-see at the connections and on the main board and immediate area. 
Look for a crusty appearance that may indicate corrosion between two
contacts.  Look for a tiny solder blob that may be shorting the clock or
reset pins.  See if rewetting the socket helps.  For checking the
connections, use a toothbrush to get under the socket and around each
pin to see if there is something to be dislodged.  Look for a blob of
corrosion or solder.

Thankx,
Ed

Wayne Stewart wrote:
> Good idea but after pulling the rest of the cards I tried a regular 65816 with no luck. Some time ago I replaced the socket with a machine contact socket. Back then I had doubts about a regular socket making solid contact with the cable.


          /=============\                     /=============\
       VP  I1          40I RES            Vss  I1          40I RES
      RDY  I2          39I VDA            RDY  I2          39I o2 (OUT)
    ABORT  I3          38I M/X       o1 (OUT)  I3          38I SO
      IRQ  I4          37I o2 (IN)        IRQ  I4          37I o2 (IN)
       ML  I5          36I BE              NC  I5          36I NC
      NMI  I6          35I E              NMI  I6          35I NC
      VPA  I7          34I R/W           SYNC  I7          34I R/W
      VDD  I8          33I D0/BA0         Vdd  I8          33I D0
       A0  I9  W65C816 32I D1/BA1          A0  I9   6502   32I D1
       A1  I10         31I D2/BA2          A1  I10         31I D2
       A2  I11         30I D3/BA3          A2  I11         30I D3
       A3  I12         29I D4/BA4          A3  I12         29I D4
       A4  I13         28I D5/BA5          A4  I13         28I D5
       A5  I14         27I D6/BA6          A5  I14         27I D6
       A6  I15         26I D7/BA7          A6  I15         26I D7
       A7  I16         25I A15             A7  I16         25I A15
       A8  I17         24I A14             A8  I17         24I A14
       A9  I18         23I A13             A9  I18         23I A13
      A10  I19         22I A12            A10  I19         22I A12
      A11  I20         21I Vss            A11  I20         21I Vss
           \=============/                     \=============/