add floppsy support - working!

```
greaseweazle>python3 gw read --device COM15 --format ibm.1440 ouuut.img
*** WARNING: Optimised data routines not found: Run scripts/setup.sh
Reading c=0-79:h=0-1 revs=2
Format ibm.1440
T0.0: IBM MFM (18/18 sectors) from Raw Flux (179537 flux in 402.62ms)
T0.1: IBM MFM (18/18 sectors) from Raw Flux (185345 flux in 402.67ms)
T1.0: IBM MFM (18/18 sectors) from Raw Flux (160448 flux in 402.30ms)
T1.1: IBM MFM (18/18 sectors) from Raw Flux (149618 flux in 402.15ms)
T2.0: IBM MFM (18/18 sectors) from Raw Flux (150098 flux in 402.17ms)
T2.1: IBM MFM (18/18 sectors) from Raw Flux (149949 flux in 402.14ms)
T3.0: IBM MFM (18/18 sectors) from Raw Flux (150636 flux in 402.15ms)
```

examples/greaseweazle/greaseweazle.ino

@@ -28,9 +28,6 @@
 #define READ_PIN 9     // IDC 30
 #define SIDE_PIN 8     // IDC 32
 #define READY_PIN 7    // IDC 34
-#ifndef USE_TINYUSB
-#error "Please set Adafruit TinyUSB under Tools > USB Stack"
-#endif
 #elif defined(ARDUINO_RASPBERRY_PI_PICO)
 #define DENSITY_PIN 2 // IDC 2
 #define INDEX_PIN 3   // IDC 8
@@ -45,13 +42,15 @@
 #define READ_PIN 12   // IDC 30
 #define SIDE_PIN 13   // IDC 32
 #define READY_PIN 14  // IDC 34
-#ifndef USE_TINYUSB
-#error "Please set Adafruit TinyUSB under Tools > USB Stack"
-#endif
+#elif defined(ARDUINO_ADAFRUIT_FLOPPSY_RP2040)
+// Yay built in pin definitions!
 #else
 #error "Please set up pin definitions!"
 #endif
 
+#ifndef USE_TINYUSB
+#error "Please set Adafruit TinyUSB under Tools > USB Stack"
+#endif
 
 #if defined (ARDUINO_ADAFRUIT_FEATHER_RP2040)
 // jepler's prototype board, subject to change
@@ -165,6 +164,14 @@ bool setbustype(int bustype) {
 void setup() {
   Serial.begin(115200);
   Serial1.begin(115200);
+
+#if defined(FLOPPY_DIRECTION_PIN)
+  pinMode(FLOPPY_DIRECTION_PIN, OUTPUT);
+  digitalWrite(FLOPPY_DIRECTION_PIN, HIGH);
+#endif
+
+  delay(100);
+
   //while (!Serial) delay(100);
   Serial1.println("GrizzlyWizzly");
 
@@ -675,4 +682,4 @@ needfloppy:
   Serial.write(reply_buffer, 2);
 
   //Serial1.println("cmd complete!");
-}
+}