diff --git a/justfile b/justfile
index b77f868..d2affd8 100644
--- a/justfile
+++ b/justfile
@@ -1,2 +1,6 @@
 build:
   cargo build
+
+rerun:
+  probe-rs reset --chip RP2040
+  probe-rs attach --chip RP2040 target/thumbv6m-none-eabi/debug/co2_sensing
diff --git a/src/main.rs b/src/main.rs
index 27b1c7f..ba39ca8 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -13,9 +13,8 @@ use embassy_executor::Spawner;
 use embassy_rp::spi::Spi;
 use embassy_rp::{gpio, spi};
 use embedded_hal_bus::spi::ExclusiveDevice;
-use embedded_sdmmc::fat::Bpb;
 use embedded_sdmmc::sdcard::{DummyCsPin, SdCard};
-use embedded_sdmmc::{Block, BlockCount, BlockDevice, BlockIdx, FatVolume, VolumeIdx, VolumeType};
+use embedded_sdmmc::{Block, BlockDevice, BlockIdx, VolumeIdx};
 use gpio::{Level, Output};
 use {defmt_rtt as _, panic_probe as _};
 
@@ -61,8 +60,13 @@ async fn main(_spawner: Spawner) {
     let mut volume_mgr = embedded_sdmmc::VolumeManager::new(sdcard, DummyTimesource());
     {
         let device = volume_mgr.device();
-        let info = read_volume_label(device, VolumeIdx(0)).unwrap();
-        info!("Volume 0: name: {:?}", core::str::from_utf8(&info).unwrap());
+        for (index, label) in valid_volumes(device).into_iter().flatten() {
+            info!(
+                "Volume {}: name: {:?}",
+                index.0,
+                core::str::from_utf8(&label).unwrap()
+            );
+        }
     }
 
     // Try and access Volume 0 (i.e. the first partition).
@@ -102,6 +106,19 @@ async fn main(_spawner: Spawner) {
     info!("Program end")
 }
 
+pub fn valid_volumes<D>(block_device: &mut D) -> [Option<(VolumeIdx, [u8; 11])>; 4]
+where
+    D: BlockDevice,
+{
+    let mut res = [None; 4];
+    for i in 0..4 {
+        let index_and_label = read_volume_label(block_device, VolumeIdx(i))
+            .ok()
+            .map(|label| (VolumeIdx(i), label));
+        res[i] = index_and_label;
+    }
+    res
+}
 /// Read out the volume label a partition
 ///
 /// I mostly pulled out some interiors of `embedded_sdmmc` and plugged
@@ -125,7 +142,6 @@ where
     const PARTITION_INFO_STATUS_INDEX: usize = 0;
     const PARTITION_INFO_TYPE_INDEX: usize = 4;
     const PARTITION_INFO_LBA_START_INDEX: usize = 8;
-    const PARTITION_INFO_NUM_BLOCKS_INDEX: usize = 12;
     /// Marker for a FAT32 partition. Sometimes also use for FAT16 formatted
     /// partitions.
     const PARTITION_ID_FAT32_LBA: u8 = 0x0C;
@@ -138,7 +154,7 @@ where
     /// use.
     const PARTITION_ID_FAT32_CHS_LBA: u8 = 0x0B;
 
-    let (part_type, lba_start, num_blocks) = {
+    let (part_type, lba_start) = {
         let mut blocks = [Block::new()];
         block_device
             .read(&mut blocks, BlockIdx(0), "read_mbr")
@@ -165,14 +181,7 @@ where
         let lba_start = LittleEndian::read_u32(
             &partition[PARTITION_INFO_LBA_START_INDEX..(PARTITION_INFO_LBA_START_INDEX + 4)],
         );
-        let num_blocks = LittleEndian::read_u32(
-            &partition[PARTITION_INFO_NUM_BLOCKS_INDEX..(PARTITION_INFO_NUM_BLOCKS_INDEX + 4)],
-        );
-        (
-            partition[PARTITION_INFO_TYPE_INDEX],
-            BlockIdx(lba_start),
-            BlockCount(num_blocks),
-        )
+        (partition[PARTITION_INFO_TYPE_INDEX], BlockIdx(lba_start))
     };
     match part_type {
         PARTITION_ID_FAT32_CHS_LBA