add readme and volume label to fat. unplug disk on eject by host. support visualizing binary frame dump file.

firmware/src/fat_disk.c

 
 #include <string.h>
 #include <stdlib.h>
+#include <stdio.h>
 
 #include "pico/stdlib.h"
 #include "ff.h"
 
 #include "config.h"
 #include "log.h"
+#include "debug.h"
 #include "fat_disk.h"
 
 static uint8_t disk[DISK_BLOCK_COUNT * DISK_BLOCK_SIZE];
         debug("error: f_mkfs returned %d", res);
         return;
     }
+
+    if (debug_msc_mount() != 0) {
+        debug("error mounting disk");
+        return;
+    }
+
+    // maximum length: 11 bytes
+    f_setlabel("DEBUG DISK");
+
+    FIL file;
+    res = f_open(&file, "README.md", FA_CREATE_ALWAYS | FA_WRITE);
+    if (res != FR_OK) {
+        debug("error: f_open returned %d", res);
+    } else {
+        char readme[1024];
+        size_t pos = 0;
+        pos += snprintf(readme + pos, 1024 - pos, "# Trackball\r\n");
+        pos += snprintf(readme + pos, 1024 - pos, "\r\n");
+        pos += snprintf(readme + pos, 1024 - pos, "Project by Thomas Buck <thomas@xythobuz.de>\r\n");
+        pos += snprintf(readme + pos, 1024 - pos, "Licensed under GPLv3.\r\n");
+        pos += snprintf(readme + pos, 1024 - pos, "Source at https://git.xythobuz.de/thomas/Trackball\r\n");
+
+        size_t len = strlen(readme);
+        UINT bw;
+        res = f_write(&file, readme, len, &bw);
+        if ((res != FR_OK) || (bw != len)) {
+            debug("error: f_write returned %d", res);
+        }
+
+        res = f_close(&file);
+        if (res != FR_OK) {
+            debug("error: f_close returned %d", res);
+        }
+    }
+
+    if (debug_msc_unmount() != 0) {
+        debug("error unmounting disk");
+    }
 }
 
 uint8_t *fat_disk_get_sector(uint32_t sector) {

firmware/src/usb_msc.c

 /* 
- * The MIT License (MIT)
+ * Extended from TinyUSB example code.
+ * Copyright (c) 2022 Thomas Buck (thomas@xythobuz.de)
  *
+ * The MIT License (MIT)
  * Copyright (c) 2019 Ha Thach (tinyusb.org)
  *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  * THE SOFTWARE.
- *
  */
 
 #include "bsp/board.h"
 // Invoked when received Test Unit Ready command.
 // return true allowing host to read/write this LUN e.g SD card inserted
 bool tud_msc_test_unit_ready_cb(uint8_t lun) {
-    if (ejected || !medium_available) {
+    if (!medium_available) {
         // Additional Sense 3A-00 is NOT_FOUND
         tud_msc_set_sense(lun, SCSI_SENSE_NOT_READY, 0x3a, 0x00);
-        return false;
     }
 
-    return true;
+    return medium_available;
 }
 
 // Invoked when received SCSI_CMD_READ_CAPACITY_10 and
 void tud_msc_capacity_cb(uint8_t lun, uint32_t* block_count, uint16_t* block_size) {
     (void) lun;
 
-    *block_count = DISK_BLOCK_COUNT;
-    *block_size  = DISK_BLOCK_SIZE;
+    if (!medium_available) {
+        *block_count = 0;
+        *block_size = 0;
+    } else {
+        *block_count = DISK_BLOCK_COUNT;
+        *block_size  = DISK_BLOCK_SIZE;
+    }
 }
 
 // Invoked when received Start Stop Unit command
     } else {
         // unload disk storage
         debug("unload disk storage %d", load_eject);
-        ejected = true;
+        if (load_eject) {
+            medium_available = false;
+        }
     }
 
     return true;
     bool in_xfer = true;
 
     switch (scsi_cmd[0]) {
+    case 0x1E:
+        // Prevent/Allow Medium Removal
+        if (scsi_cmd[4] & 0x01) {
+            // Prevent medium removal
+            if (!medium_available) {
+                debug("Host wants to lock non-existing medium. Not supported.");
+                resplen = -1;
+            } else {
+                debug("Host wants to lock medium.");
+            }
+        } else {
+            // Allow medium removal
+            if (medium_available) {
+                debug("Host ejected medium. Unplugging disk.");
+                medium_available = false;
+            } else {
+                debug("host ejected non-existing medium. Not supported.");
+                resplen = -1;
+            }
+        }
+        break;
+
     default:
         // Set Sense = Invalid Command Operation
         tud_msc_set_sense(lun, SCSI_SENSE_ILLEGAL_REQUEST, 0x20, 0x00);

firmware/util/visualize_frame.py

 import numpy as np
 import sys
 import math
+import os
 
 if len(sys.argv) < 2:
     print("Usage:")
     print("reading " + sys.argv[n + 1])
 
     frame = []
-    with open(sys.argv[n + 1]) as f:
-        lines = f.readlines()
-        for line in lines:
-            nums = line.split()
-            for r in nums:
-                frame.append(int(r, 16))
+    if os.path.getsize(sys.argv[n + 1]) == 1296:
+        print("binary file format detected. parsing.")
+        with open(sys.argv[n + 1], "rb") as f:
+            while (byte := f.read(1)):
+                frame.append(int.from_bytes(byte, "big"))
+    else:
+        print("text file format detected. parsing.")
+        with open(sys.argv[n + 1]) as f:
+            lines = f.readlines()
+            for line in lines:
+                nums = line.split()
+                for r in nums:
+                    frame.append(int(r, 16))
 
     print("frame length: " + str(len(frame)))
     row_len = math.sqrt(len(frame))