diff -r 89fc3c57282e -r e0f50087c909 main/task_sdcard.c
--- a/main/task_sdcard.c	Wed Jun 26 21:48:49 2024 +0200
+++ b/main/task_sdcard.c	Fri Jun 28 15:33:24 2024 +0200
@@ -467,6 +467,7 @@
     ESP_LOGI(TAG, "Start SD card");
     sdmmc_host_t host = SDSPI_HOST_DEFAULT();
     host.slot = SDCARD_HOST_SLOT;	// HSPI_HOST is in use by the TFT.
+    host.max_freq_khz = 20000;		// 20 MHz speed limit.
     spi_bus_config_t bus_cfg = {
         .mosi_io_num = SDCARD_PIN_NUM_MOSI,
         .miso_io_num = SDCARD_PIN_NUM_MISO,
@@ -489,6 +490,18 @@
     slot_config.host_id     = host.slot;
 
     /*
+     * Since IDF 5.0 the SD card is dead slow. Use pullup resistors
+     * on the board, see schematic.
+     * Or just use gpio pullup as workaround.
+     * Or both (not tested).
+     * See https://github.com/espressif/esp-idf/issues/10493
+     */
+    gpio_set_pull_mode(SDCARD_PIN_NUM_MOSI, GPIO_PULLUP_ONLY);
+    gpio_set_pull_mode(SDCARD_PIN_NUM_MISO, GPIO_PULLUP_ONLY);
+    gpio_set_pull_mode(SDCARD_PIN_NUM_CLK, GPIO_PULLUP_ONLY);
+    gpio_set_pull_mode(SDCARD_PIN_NUM_CS, GPIO_PULLUP_ONLY);
+
+    /*
      * No errors from the sdspi_transaction driver.
      */
     esp_log_level_set("sdspi_transaction", ESP_LOG_NONE);
@@ -506,10 +519,10 @@
 
     ret = my_vfs_fat_sdspi_init("/sdcard", &host, &slot_config);
     if (ret == ESP_OK) {
-	ESP_LOGI(TAG, "SPI card interface ready");
+	ESP_LOGI(TAG, "SD card interface ready");
 	sdcard_state->host_ok = true;
     } else {
-	ESP_LOGE(TAG, "SPI card interface failed, abort task");
+	ESP_LOGE(TAG, "SD card interface failed: %s, abort task", esp_err_to_name(ret));
 	vTaskDelete(NULL);
 	return;
     }