Proper technique needed to nest a setWatch() within a separate setWatch()

Thr 2019.08.01

Seeking technique suggestions here. Individually, manual toggle of lines allows correct result from one pass of setWatch().

Continuation of threads:

Espruino Wifi as USB Master, Pico as USB slave - is that possible?
Does pinMode 'input' state place pin in tri-state mode

Goal: After CS Chip Select goes low, on rising edge of SCK clock line, read state of MOSI

Setup: Espruino MDBT42Q as master sending software SPI to Espruino WiFi as slave

Data sent inside a setInterval() creating a CS pulse Low of ~200msec surounding 4 x 8bits of ~300usec clocked at 3usec:

Limited code for brevity

spi.setup( { mosi:D27, miso:D26, sck:D25, baud:100000 } );
  ...
  digitalWrite(PIN_CS,0);

  var val = spi.send([0xC0,0xF4,3,4]);

  digitalWrite(PIN_CS,1);

Verified: Using logic analyzer and protocol decoder am able to see and verify CS, SCK, MOSI, MISO and data as placed on MOSI

Individually, the setWatch() definitions execute as expected.

// WiFi
const MOSI = B5;  // pin 17
const MISO = B4;  // pin 16
const SCK  = B3;  // pin 15
const CS   = B1;  // pin  7


setWatch(function(e) { 
  // watchdog to prevent runaway
  if( countWatch >= 10 ) clearWatch();
  countWatch++;
  console.log(e.time-e.lastTime);
  }, B3, { repeat:true, edge:'falling' }
);



read:  0.00000286102
calc:  SPI 100000 1usec pulse 2usec  500KHz

The idea is to only allow the second setWatch() to run after tripped by the setWatch() monitoring CS

var state;

//Start first: setw()

//Chip Select detect
function setcs() {
  setWatch(function(e) { 
    console.log(e.time-e.lastTime);

    // new attempt to signal 2nd setWatch()
    state = 0;

//ABANDONED as second setWatch() always returns 0's
//    var state = digitalRead( CS );
//    if( !state )
//      fetchBit();

    }, B1, { repeat:true, edge:'falling' }
//    }, B1, { repeat:true, edge:'rising' }
  );
}




// Monitor clock line
function setw() {
  setWatch(function(e) {
    // watchdog to prevent runaway
    if( countWatch >= 10 ) clearWatch();
    countWatch++;
//  console.log(e.time-e.lastTime);

//    var state = digitalRead( CS );
    if( !state )
      fetchBit();

//    }, B3, { repeat:true, edge:'falling' }
    }, B3, { repeat:true, edge:'rising' }
  );
}

When I manually set the state of MOSI using

  digitalWrite(MOSI,0);
  digitalWrite(MOSI,1);



function fetchBit() {
  var val = 0x00;
  val = digitalRead( MOSI );  // B5
  aryByteCmd[ elemBits++ ] = val;
    ...

function fetchBit() reads and stores manually, correctly.

Suspicion: A timing issue, starting technique or a different means to trigger the second setWatch() is needed.