[Mark1960]

Colin, when looking for activity on R/W and related signals switch your scope to trigger on falling edge.

After the initial burst of writes there will only be brief intermittent negative pulses on the R/W signals and your scope trigger on positive edge might not display the negative pulse.

Edit: Also change the trigger level back to 1.4v, your last set of traces look like they were triggering on negative overshoot, and there might not be enough overshoot on all the signals.