diff --git a/README.md b/README.md
index 9314b73..309d81c 100644
--- a/README.md
+++ b/README.md
@@ -123,7 +123,7 @@ The player plays the MP3 files of `music/` on the card. Copy them there on a
 PC, or send them over the console:
 
 ```bash
-scripts/ymodem_send.py --dest /mnt/dmsdio0_0p1/music *.mp3
+scripts/ymodem_send.py --dest music *.mp3
 ```
 
 carhmi reads the directory when it starts: restart it (`service restart carhmi`)
@@ -317,6 +317,12 @@ the SD card) to the device over its UART console, with YMODEM: dmell's
 no pyserial needed) types it and sends the files - their paths kept under
 the destination directory.
 
+The files go to the SD card: the script asks the device what is mounted in
+`/mnt` - automount mounts a card at `/mnt/<label>`, or `/mnt/<node name>`
+without one (`/mnt/dmsdio0_0p1`) - and sends them there when there is one
+card. With several, `DMBOOT_UPLOAD_CARD` names it; an absolute
+`DMBOOT_UPLOAD_DEST` is used as it is.
+
 - `upload-files` - to a device that is running
 - `install-all` - `install-firmware`, then the files once the device has started
 
@@ -328,7 +334,8 @@ cmake --build . --target upload-files
 |----------|---------|-------------|
 | `DMBOOT_UPLOAD_PORT` | `/dev/ttyACM0` | The device's console |
 | `DMBOOT_UPLOAD_BAUD` | `921600` | Its baud rate |
-| `DMBOOT_UPLOAD_DEST` | `/mnt/dmsdio0_0p1` | Directory on the device |
+| `DMBOOT_UPLOAD_DEST` | empty | Directory on the card (relative, empty: its root), or an absolute one |
+| `DMBOOT_UPLOAD_CARD` | `auto` | The card: its name in `/mnt`, `auto` (the one there is), `none` (the shell's directory) |
 | `DMBOOT_UPLOAD_SOURCES` | `build/sdcard` | Files and directories (`SRC=NAME` sends SRC as NAME) |
 | `DMBOOT_UPLOAD_BLOCK` | `1024` | YMODEM block size (128 or 1024) |
 | `DMBOOT_UPLOAD_WAIT` | `60` | `install-all`: seconds the device may take to start |
@@ -336,5 +343,7 @@ cmake --build . --target upload-files
 The script works on its own too:
 
 ```bash
-scripts/ymodem_send.py --dest /mnt/dmsdio0_0p1/views view.dmv fonts/
+scripts/ymodem_send.py --dest views view.dmv fonts/            # views/ on the card
+scripts/ymodem_send.py --card bootfs --dest views view.dmv      # of the card in /mnt/bootfs
+scripts/ymodem_send.py --dest /mnt/sd/views view.dmv            # an absolute directory
 ```
diff --git a/scripts/targets.cmake b/scripts/targets.cmake
index 4c64868..a39195d 100644
--- a/scripts/targets.cmake
+++ b/scripts/targets.cmake
@@ -161,9 +161,13 @@ add_custom_target(debug
 # `ymodem` command receives them (scripts/ymodem_send.py types it).
 #   upload-files   the files, to the device running (its console on DMBOOT_UPLOAD_PORT)
 #   install-all    the firmware, then the files (waiting for the device to start)
+# They go to the SD card the script finds on the device (in /mnt, where
+# automount mounts it by its label or node name) - or to an absolute
+# DMBOOT_UPLOAD_DEST.
 set(DMBOOT_UPLOAD_PORT "/dev/ttyACM0" CACHE STRING "Serial port of the device's dmell console the files are sent over (upload-files)")
 set(DMBOOT_UPLOAD_BAUD "921600" CACHE STRING "Baud rate of DMBOOT_UPLOAD_PORT")
-set(DMBOOT_UPLOAD_DEST "/mnt/dmsdio0_0p1" CACHE STRING "Directory on the device the uploaded files go to (their paths under it)")
+set(DMBOOT_UPLOAD_DEST "" CACHE STRING "Directory the uploaded files go to (their paths under it): on the SD card (relative; empty: its root), or absolute")
+set(DMBOOT_UPLOAD_CARD "auto" CACHE STRING "The card a relative DMBOOT_UPLOAD_DEST is on: its name in /mnt, auto (the one the device has), none (the shell's directory)")
 set(DMBOOT_UPLOAD_SOURCES "${CMAKE_BINARY_DIR}/sdcard" CACHE STRING "Files and directories uploaded (semicolon-separated; SRC=NAME puts SRC as NAME); default: build/sdcard")
 set(DMBOOT_UPLOAD_BLOCK "1024" CACHE STRING "YMODEM block size, 128 or 1024")
 set(DMBOOT_UPLOAD_WAIT "60" CACHE STRING "install-all: seconds the device may take to start before it receives the files")
@@ -171,17 +175,27 @@ set(DMBOOT_UPLOAD_WAIT "60" CACHE STRING "install-all: seconds the device may ta
 find_package(Python3 COMPONENTS Interpreter QUIET)
 if(Python3_Interpreter_FOUND)
     set(DMBOOT_UPLOAD_COMMAND ${Python3_EXECUTABLE} ${CMAKE_CURRENT_SOURCE_DIR}/scripts/ymodem_send.py
-        --port ${DMBOOT_UPLOAD_PORT} --baud ${DMBOOT_UPLOAD_BAUD} --dest ${DMBOOT_UPLOAD_DEST} --block ${DMBOOT_UPLOAD_BLOCK})
+        --port ${DMBOOT_UPLOAD_PORT} --baud ${DMBOOT_UPLOAD_BAUD} --card ${DMBOOT_UPLOAD_CARD} --block ${DMBOOT_UPLOAD_BLOCK})
+    if(NOT "${DMBOOT_UPLOAD_DEST}" STREQUAL "")
+        list(APPEND DMBOOT_UPLOAD_COMMAND --dest ${DMBOOT_UPLOAD_DEST})
+    endif()
+    if("${DMBOOT_UPLOAD_DEST}" MATCHES "^/")
+        set(DMBOOT_UPLOAD_WHERE "${DMBOOT_UPLOAD_DEST}")
+    else()
+        set(DMBOOT_UPLOAD_WHERE "the SD card (${DMBOOT_UPLOAD_CARD})/${DMBOOT_UPLOAD_DEST}")
+    endif()
+    # (build/sdcard - the sdcard modules - is made by download_sdcard_modules: first)
     add_custom_target(upload-files
         COMMAND ${DMBOOT_UPLOAD_COMMAND} ${DMBOOT_UPLOAD_SOURCES}
+        DEPENDS download_sdcard_modules
         USES_TERMINAL
-        COMMENT "Uploading files to ${DMBOOT_UPLOAD_DEST} over ${DMBOOT_UPLOAD_PORT} (YMODEM)..."
+        COMMENT "Uploading files to ${DMBOOT_UPLOAD_WHERE} over ${DMBOOT_UPLOAD_PORT} (YMODEM)..."
     )
     add_custom_target(install-all
         COMMAND ${DMBOOT_UPLOAD_COMMAND} --wait ${DMBOOT_UPLOAD_WAIT} ${DMBOOT_UPLOAD_SOURCES}
-        DEPENDS install-firmware
+        DEPENDS install-firmware download_sdcard_modules
         USES_TERMINAL
-        COMMENT "Uploading files to ${DMBOOT_UPLOAD_DEST} once ${TARGET} has started..."
+        COMMENT "Uploading files to ${DMBOOT_UPLOAD_WHERE} once ${TARGET} has started..."
     )
 else()
     message(STATUS "Python 3 not found - the upload-files and install-all targets are not available")
diff --git a/scripts/ymodem_send.py b/scripts/ymodem_send.py
index 5d31b5a..e6a4600 100755
--- a/scripts/ymodem_send.py
+++ b/scripts/ymodem_send.py
@@ -5,9 +5,14 @@
 types `ymodem recv -d DEST` into the console, waits for the receiver's
 'C' and sends every file - its name (with directories) under DEST:
 
-    ymodem_send.py --port /dev/ttyACM0 --dest /mnt/dmsdio0_0p1 build/sdcard
-    ymodem_send.py --dest /mnt/dmsdio0_0p1/views view.dmv fonts/
-    ymodem_send.py --dest /mnt/sd local/dir=remote/dir
+    ymodem_send.py build/sdcard                         (the card's root)
+    ymodem_send.py --dest views view.dmv fonts/         (views/ on the card)
+    ymodem_send.py --dest /mnt/sd local/dir=remote/dir  (that directory)
+
+A DEST that is not absolute is on the SD card: the card is found on the
+device - `ls /mnt`, where automount mounts every card (/mnt/<label>, or
+/mnt/<node name>) - when it has one; --card NAME picks one of several,
+--card none sends under the shell's current directory instead.
 
 A FILE is sent by its name, a DIR with everything in it (names relative
 to it), SRC=NAME as NAME (a directory: under NAME). Only the standard
@@ -16,6 +21,7 @@
 
 import argparse
 import os
+import re
 import select
 import sys
 import termios
@@ -179,6 +185,52 @@ def receiver_ready(link, command, timeout):
     return False
 
 
+def mounted_cards(link):
+    """What /mnt holds on the device - the cards automount mounted"""
+    link.write(b'\r')
+    link.drain()
+    link.write(b'ls /mnt\r')
+    said = link.drain(0.5).decode(errors='replace')
+    said = re.sub(r'\x1b\[[0-9;]*[A-Za-z]', '', said)
+    if 'ls /mnt' not in said or 'ERROR' in said:
+        return []                       # (the shell not answering yet - starting -, or no /mnt)
+    said = said.split('ls /mnt', 1)[1]                      # (what the echo is followed by - it may run into it)
+    said = re.sub(r'\S*@\S*>', '', said)                   # (the prompts)
+    names = []
+    for line in said.replace('\r', '\n').split('\n'):
+        names += [n for n in re.split(r'\s{2,}', line.strip()) if n]
+    return [n for n in names if re.fullmatch(r'[\x21-\x7e][\x20-\x7e]*', n)]   # (not what the line had before)
+
+
+def find_card(link, card, wait, log):
+    """The card's directory: CARD, or the one card mounted - looked for again for `wait` seconds"""
+    until = time.monotonic() + wait
+    while True:
+        cards = mounted_cards(link)
+        if card != 'auto' and card in cards:
+            return f'/mnt/{card}'
+        if card == 'auto' and len(cards) == 1:
+            return f'/mnt/{cards[0]}'
+        if card == 'auto' and len(cards) > 1:
+            raise Failure(f'more than one card on the device ({", ".join(cards)}): pick one with --card, '
+                          'or give an absolute --dest')
+        if time.monotonic() >= until:
+            what = f'no card {card} in /mnt' if card != 'auto' else 'no card mounted in /mnt'
+            raise Failure(f'{what} (found: {", ".join(cards) or "nothing"}) - is the card in, formatted (FAT)?')
+        log('  waiting for the card ...')
+        time.sleep(2.0)
+
+
+def destination(link, args, log):
+    """Where the files go: --dest as it is (absolute), or under the card"""
+    if args.dest.startswith('/') or args.card == 'none':
+        return args.dest
+    root = find_card(link, args.card, args.wait, log)
+    dest = f'{root}/{args.dest.strip("/")}' if args.dest.strip('/') else root
+    log(f'  to {dest}')
+    return dest
+
+
 def files_of(sources):
     """(local path, name sent) of every source"""
     out = []
@@ -205,7 +257,11 @@ def main():
     ap.add_argument('sources', nargs='+', help='FILE, DIR or SRC=NAME')
     ap.add_argument('--port', default='/dev/ttyACM0', help='the device console (default /dev/ttyACM0)')
     ap.add_argument('--baud', type=int, default=921600)
-    ap.add_argument('--dest', default='', help='the directory on the device the names are under')
+    ap.add_argument('--dest', default='', help='the directory on the device the names are under: absolute, '
+                    'or on the SD card (default: the card\'s root)')
+    ap.add_argument('--card', default='auto', metavar='NAME',
+                    help='the card a relative --dest is on: its name in /mnt (auto: the one there is; none: '
+                    'under the shell\'s current directory)')
     ap.add_argument("--block", type=int, choices=(128, 1024), default=1024,
                     help='YMODEM block size (default 1024)')
     ap.add_argument('--no-command', action='store_true', help='ymodem recv is already running')
@@ -227,7 +283,8 @@ def progress(name, sent, size):
         if args.no_command:
             wait_for(link, (CRC,), 15.0, 'the receiver')
         else:
-            command = f'ymodem recv -d {args.dest}' if args.dest else 'ymodem recv'
+            dest = destination(link, args, log)
+            command = f'ymodem recv -d {dest}' if dest else 'ymodem recv'
             until = time.monotonic() + args.wait
             while True:
                 link.write(b'\r')