Switch to latest toolchain.

Tune the timing for the readDataLoop with the latest toolchain.

platformio.ini

@@ -17,7 +17,7 @@ upload_protocol = stlink
 ; 1.80201.181220 ; 921kb/sec
 ; 1.90201.191206 ; 912kb/sec
 ; 1.90301.200702 ; default - 955kb/sec
-platform_packages = toolchain-gccarmnoneeabi@1.60301.0
+platform_packages = toolchain-gccarmnoneeabi
 
 build_unflags = 
     -Os

src/BlueSCSI.cpp

@@ -878,7 +878,7 @@ void readDataLoop(uint32_t blockSize)
     REQ_OFF();
     *dstptr++ = ~(ret >> 8);
     // Move wait loop in to a single 8 byte prefetch buffer
-    asm("nop.w");
+    asm("nop.w;nop");
     WAIT_ACK_INACTIVE();
     REQ_ON();
     // Extra 1 cycle delay