diff --git a/pico-keys-sdk b/pico-keys-sdk
index 151ae5f..88071e1 160000
--- a/pico-keys-sdk
+++ b/pico-keys-sdk
@@ -1 +1 @@
-Subproject commit 151ae5fae4c5815042fce5d5cbcc06d76561dc9c
+Subproject commit 88071e117222bbc3ab018bc45f6d691a4fcf78f3
diff --git a/src/fido/cbor_client_pin.c b/src/fido/cbor_client_pin.c
index c7c13d8..0e3d6e9 100644
--- a/src/fido/cbor_client_pin.c
+++ b/src/fido/cbor_client_pin.c
@@ -169,7 +169,7 @@ int ecdh(uint8_t protocol, const mbedtls_ecp_point *Q, uint8_t *sharedSecret) {
 int resetPinUvAuthToken() {
     uint8_t t[32];
     random_gen(NULL, t, sizeof(t));
-    flash_write_data_to_file(ef_authtoken, t, sizeof(t));
+    file_put_data(ef_authtoken, t, sizeof(t));
     paut.permissions = 0;
     paut.data = file_get_data(ef_authtoken);
     paut.len = file_get_size(ef_authtoken);
@@ -417,7 +417,7 @@ int cbor_client_pin(const uint8_t *data, size_t len) {
         hsh[0] = MAX_PIN_RETRIES;
         hsh[1] = pin_len;
         mbedtls_md(mbedtls_md_info_from_type(MBEDTLS_MD_SHA256), paddedNewPin, pin_len, hsh + 2);
-        flash_write_data_to_file(ef_pin, hsh, 2 + 16);
+        file_put_data(ef_pin, hsh, 2 + 16);
         low_flash_available();
         goto err; //No return
     }
@@ -464,7 +464,7 @@ int cbor_client_pin(const uint8_t *data, size_t len) {
         uint8_t pin_data[18];
         memcpy(pin_data, file_get_data(ef_pin), 18);
         pin_data[0] -= 1;
-        flash_write_data_to_file(ef_pin, pin_data, sizeof(pin_data));
+        file_put_data(ef_pin, pin_data, sizeof(pin_data));
         low_flash_available();
         uint8_t retries = pin_data[0];
         uint8_t paddedNewPin[64];
@@ -489,7 +489,7 @@ int cbor_client_pin(const uint8_t *data, size_t len) {
             }
         }
         pin_data[0] = MAX_PIN_RETRIES;
-        flash_write_data_to_file(ef_pin, pin_data, sizeof(pin_data));
+        file_put_data(ef_pin, pin_data, sizeof(pin_data));
         low_flash_available();
         new_pin_mismatches = 0;
         ret = decrypt(pinUvAuthProtocol, sharedSecret, newPinEnc.data, newPinEnc.len, paddedNewPin);
@@ -520,12 +520,12 @@ int cbor_client_pin(const uint8_t *data, size_t len) {
             memcmp(hsh + 2, file_get_data(ef_pin) + 2, 16) == 0) {
             CBOR_ERROR(CTAP2_ERR_PIN_POLICY_VIOLATION);
         }
-        flash_write_data_to_file(ef_pin, hsh, 2 + 16);
+        file_put_data(ef_pin, hsh, 2 + 16);
         if (file_has_data(ef_minpin) && file_get_data(ef_minpin)[1] == 1) {
             uint8_t *tmp = (uint8_t *) calloc(1, file_get_size(ef_minpin));
             memcpy(tmp, file_get_data(ef_minpin), file_get_size(ef_minpin));
             tmp[1] = 0;
-            flash_write_data_to_file(ef_minpin, tmp, file_get_size(ef_minpin));
+            file_put_data(ef_minpin, tmp, file_get_size(ef_minpin));
             free(tmp);
         }
         low_flash_available();
@@ -573,7 +573,7 @@ int cbor_client_pin(const uint8_t *data, size_t len) {
         uint8_t pin_data[18];
         memcpy(pin_data, file_get_data(ef_pin), 18);
         pin_data[0] -= 1;
-        flash_write_data_to_file(ef_pin, pin_data, sizeof(pin_data));
+        file_put_data(ef_pin, pin_data, sizeof(pin_data));
         low_flash_available();
         uint8_t retries = pin_data[0];
         uint8_t paddedNewPin[64], poff = (pinUvAuthProtocol - 1) * IV_SIZE;
@@ -599,7 +599,7 @@ int cbor_client_pin(const uint8_t *data, size_t len) {
         }
         pin_data[0] = MAX_PIN_RETRIES;
         new_pin_mismatches = 0;
-        flash_write_data_to_file(ef_pin, pin_data, sizeof(pin_data));
+        file_put_data(ef_pin, pin_data, sizeof(pin_data));
         low_flash_available();
         file_t *ef_minpin = search_by_fid(EF_MINPINLEN, NULL, SPECIFY_EF);
         if (file_has_data(ef_minpin) && file_get_data(ef_minpin)[1] == 1) {
diff --git a/src/fido/cbor_config.c b/src/fido/cbor_config.c
index 4026cc7..b8cb73f 100644
--- a/src/fido/cbor_config.c
+++ b/src/fido/cbor_config.c
@@ -142,9 +142,9 @@ int cbor_config(const uint8_t *data, size_t len) {
             if (has_keydev_dec == false) {
                 CBOR_ERROR(CTAP2_ERR_PIN_AUTH_INVALID);
             }
-            flash_write_data_to_file(ef_keydev, keydev_dec, sizeof(keydev_dec));
+            file_put_data(ef_keydev, keydev_dec, sizeof(keydev_dec));
             mbedtls_platform_zeroize(keydev_dec, sizeof(keydev_dec));
-            flash_write_data_to_file(ef_keydev_enc, NULL, 0); // Set ef to 0 bytes
+            file_put_data(ef_keydev_enc, NULL, 0); // Set ef to 0 bytes
             low_flash_available();
         }
         else if (vendorCommandId == CTAP_CONFIG_AUT_ENABLE) {
@@ -178,10 +178,10 @@ int cbor_config(const uint8_t *data, size_t len) {
                 CBOR_ERROR(CTAP1_ERR_INVALID_PARAMETER);
             }
 
-            flash_write_data_to_file(ef_keydev_enc, key_dev_enc, sizeof(key_dev_enc));
+            file_put_data(ef_keydev_enc, key_dev_enc, sizeof(key_dev_enc));
             mbedtls_platform_zeroize(key_dev_enc, sizeof(key_dev_enc));
-            flash_write_data_to_file(ef_keydev, key_dev_enc, file_get_size(ef_keydev)); // Overwrite ef with 0
-            flash_write_data_to_file(ef_keydev, NULL, 0); // Set ef to 0 bytes
+            file_put_data(ef_keydev, key_dev_enc, file_get_size(ef_keydev)); // Overwrite ef with 0
+            file_put_data(ef_keydev, NULL, 0); // Set ef to 0 bytes
             low_flash_available();
         }
         else {
@@ -216,7 +216,7 @@ int cbor_config(const uint8_t *data, size_t len) {
                            data + 2 + m * 32,
                            0);
         }
-        flash_write_data_to_file(ef_minpin, data, 2 + minPinLengthRPIDs_len * 32);
+        file_put_data(ef_minpin, data, 2 + minPinLengthRPIDs_len * 32);
         low_flash_available();
         goto err; //No return
     }
diff --git a/src/fido/cbor_cred_mgmt.c b/src/fido/cbor_cred_mgmt.c
index 68e95a8..f5b9fdd 100644
--- a/src/fido/cbor_cred_mgmt.c
+++ b/src/fido/cbor_cred_mgmt.c
@@ -380,7 +380,7 @@ int cbor_cred_mgmt(const uint8_t *data, size_t len) {
                             delete_file(rp_ef);
                         }
                         else {
-                            flash_write_data_to_file(rp_ef, rp_data, file_get_size(rp_ef));
+                            file_put_data(rp_ef, rp_data, file_get_size(rp_ef));
                         }
                         free(rp_data);
                         break;
diff --git a/src/fido/cbor_get_assertion.c b/src/fido/cbor_get_assertion.c
index f3a2516..87c6363 100644
--- a/src/fido/cbor_get_assertion.c
+++ b/src/fido/cbor_get_assertion.c
@@ -640,7 +640,7 @@ int cbor_get_assertion(const uint8_t *data, size_t len, bool next) {
     CBOR_CHECK(cbor_encoder_close_container(&encoder, &mapEncoder));
     resp_size = cbor_encoder_get_buffer_size(&encoder, ctap_resp->init.data + 1);
     ctr++;
-    flash_write_data_to_file(ef_counter, (uint8_t *) &ctr, sizeof(ctr));
+    file_put_data(ef_counter, (uint8_t *) &ctr, sizeof(ctr));
     low_flash_available();
 err:
     CBOR_FREE_BYTE_STRING(clientDataHash);
diff --git a/src/fido/cbor_large_blobs.c b/src/fido/cbor_large_blobs.c
index c3ebd70..432464d 100644
--- a/src/fido/cbor_large_blobs.c
+++ b/src/fido/cbor_large_blobs.c
@@ -155,7 +155,7 @@ int cbor_large_blobs(const uint8_t *data, size_t len) {
             if (expectedLength > 17 && memcmp(sha, temp_lba + expectedLength - 16, 16) != 0) {
                 CBOR_ERROR(CTAP2_ERR_INTEGRITY_FAILURE);
             }
-            flash_write_data_to_file(ef_largeblob, temp_lba, expectedLength);
+            file_put_data(ef_largeblob, temp_lba, expectedLength);
             low_flash_available();
         }
         goto err;
diff --git a/src/fido/cbor_make_credential.c b/src/fido/cbor_make_credential.c
index 44a488f..614ae5a 100644
--- a/src/fido/cbor_make_credential.c
+++ b/src/fido/cbor_make_credential.c
@@ -518,7 +518,7 @@ int cbor_make_credential(const uint8_t *data, size_t len) {
         }
     }
     ctr++;
-    flash_write_data_to_file(ef_counter, (uint8_t *) &ctr, sizeof(ctr));
+    file_put_data(ef_counter, (uint8_t *) &ctr, sizeof(ctr));
     low_flash_available();
 err:
     CBOR_FREE_BYTE_STRING(clientDataHash);
diff --git a/src/fido/cbor_vendor.c b/src/fido/cbor_vendor.c
index afe939b..d1b6f54 100644
--- a/src/fido/cbor_vendor.c
+++ b/src/fido/cbor_vendor.c
@@ -121,9 +121,9 @@ int cbor_vendor_generic(uint8_t cmd, const uint8_t *data, size_t len) {
             }
             uint8_t zeros[32];
             memset(zeros, 0, sizeof(zeros));
-            flash_write_data_to_file(ef_keydev_enc, vendorParam.data, vendorParam.len);
-            flash_write_data_to_file(ef_keydev, zeros, file_get_size(ef_keydev)); // Overwrite ef with 0
-            flash_write_data_to_file(ef_keydev, NULL, 0); // Set ef to 0 bytes
+            file_put_data(ef_keydev_enc, vendorParam.data, vendorParam.len);
+            file_put_data(ef_keydev, zeros, file_get_size(ef_keydev)); // Overwrite ef with 0
+            file_put_data(ef_keydev, NULL, 0); // Set ef to 0 bytes
             low_flash_available();
             goto err;
         }
@@ -306,7 +306,7 @@ int cbor_vendor_generic(uint8_t cmd, const uint8_t *data, size_t len) {
             }
             file_t *ef_ee_ea = search_by_fid(EF_EE_DEV_EA, NULL, SPECIFY_EF);
             if (ef_ee_ea) {
-                flash_write_data_to_file(ef_ee_ea, vendorParam.data, vendorParam.len);
+                file_put_data(ef_ee_ea, vendorParam.data, vendorParam.len);
             }
             low_flash_available();
             goto err;
diff --git a/src/fido/cmd_authenticate.c b/src/fido/cmd_authenticate.c
index 6f458d6..b3c7f9d 100644
--- a/src/fido/cmd_authenticate.c
+++ b/src/fido/cmd_authenticate.c
@@ -97,7 +97,7 @@ int cmd_authenticate() {
     res_APDU_size = 1 + 4 + olen;
 
     ctr++;
-    flash_write_data_to_file(ef_counter, (uint8_t *) &ctr, sizeof(ctr));
+    file_put_data(ef_counter, (uint8_t *) &ctr, sizeof(ctr));
     low_flash_available();
     return SW_OK();
 }
diff --git a/src/fido/credential.c b/src/fido/credential.c
index b43388b..ea44ebb 100644
--- a/src/fido/credential.c
+++ b/src/fido/credential.c
@@ -306,7 +306,7 @@ int credential_store(const uint8_t *cred_id, size_t cred_id_len, const uint8_t *
     memcpy(data, rp_id_hash, 32);
     memcpy(data + 32, cred_id, cred_id_len);
     file_t *ef = file_new(EF_CRED + sloti);
-    flash_write_data_to_file(ef, data, cred_id_len + 32);
+    file_put_data(ef, data, cred_id_len + 32);
     free(data);
 
     if (new_record == true) { //increase rps
@@ -332,7 +332,7 @@ int credential_store(const uint8_t *cred_id, size_t cred_id_len, const uint8_t *
             data = (uint8_t *) calloc(1, file_get_size(ef));
             memcpy(data, file_get_data(ef), file_get_size(ef));
             data[0] += 1;
-            flash_write_data_to_file(ef, data, file_get_size(ef));
+            file_put_data(ef, data, file_get_size(ef));
             free(data);
         }
         else {
@@ -341,7 +341,7 @@ int credential_store(const uint8_t *cred_id, size_t cred_id_len, const uint8_t *
             data[0] = 1;
             memcpy(data + 1, rp_id_hash, 32);
             memcpy(data + 1 + 32, cred.rpId.data, cred.rpId.len);
-            flash_write_data_to_file(ef, data, 1 + 32 + cred.rpId.len);
+            file_put_data(ef, data, 1 + 32 + cred.rpId.len);
             free(data);
         }
     }
diff --git a/src/fido/fido.c b/src/fido/fido.c
index 79a935d..e1ffbdb 100644
--- a/src/fido/fido.c
+++ b/src/fido/fido.c
@@ -317,7 +317,7 @@ int scan_files() {
             uint8_t kdata[32];
             int key_size = mbedtls_mpi_size(&ecdsa.d);
             mbedtls_mpi_write_binary(&ecdsa.d, kdata, key_size);
-            ret = flash_write_data_to_file(ef_keydev, kdata, key_size);
+            ret = file_put_data(ef_keydev, kdata, key_size);
             mbedtls_platform_zeroize(kdata, sizeof(kdata));
             mbedtls_ecdsa_free(&ecdsa);
             if (ret != CCID_OK) {
@@ -353,7 +353,7 @@ int scan_files() {
             if (ret <= 0) {
                 return ret;
             }
-            flash_write_data_to_file(ef_certdev, cert + sizeof(cert) - ret, ret);
+            file_put_data(ef_certdev, cert + sizeof(cert) - ret, ret);
         }
     }
     else {
@@ -363,7 +363,7 @@ int scan_files() {
     if (ef_counter) {
         if (!file_has_data(ef_counter)) {
             uint32_t v = 0;
-            flash_write_data_to_file(ef_counter, (uint8_t *) &v, sizeof(v));
+            file_put_data(ef_counter, (uint8_t *) &v, sizeof(v));
         }
     }
     else {
@@ -375,7 +375,7 @@ int scan_files() {
         if (!file_has_data(ef_authtoken)) {
             uint8_t t[32];
             random_gen(NULL, t, sizeof(t));
-            flash_write_data_to_file(ef_authtoken, t, sizeof(t));
+            file_put_data(ef_authtoken, t, sizeof(t));
         }
         paut.data = file_get_data(ef_authtoken);
         paut.len = file_get_size(ef_authtoken);
@@ -385,7 +385,7 @@ int scan_files() {
     }
     ef_largeblob = search_by_fid(EF_LARGEBLOB, NULL, SPECIFY_EF);
     if (!file_has_data(ef_largeblob)) {
-        flash_write_data_to_file(ef_largeblob,
+        file_put_data(ef_largeblob,
                                  (const uint8_t *) "\x80\x76\xbe\x8b\x52\x8d\x00\x75\xf7\xaa\xe9\x8d\x6f\xa5\x7a\x6d\x3c",
                                  17);
     }
@@ -447,7 +447,7 @@ uint8_t get_opts() {
 
 void set_opts(uint8_t opts) {
     file_t *ef = search_by_fid(EF_OPTS, NULL, SPECIFY_EF);
-    flash_write_data_to_file(ef, &opts, sizeof(uint8_t));
+    file_put_data(ef, &opts, sizeof(uint8_t));
     low_flash_available();
 }
 
diff --git a/src/fido/management.c b/src/fido/management.c
index fb305c8..f7590d0 100644
--- a/src/fido/management.c
+++ b/src/fido/management.c
@@ -130,7 +130,7 @@ int cmd_write_config() {
         return SW_WRONG_DATA();
     }
     file_t *ef = file_new(EF_DEV_CONF);
-    flash_write_data_to_file(ef, apdu.data + 1, apdu.nc - 1);
+    file_put_data(ef, apdu.data + 1, apdu.nc - 1);
     low_flash_available();
     return SW_OK();
 }
diff --git a/src/fido/oath.c b/src/fido/oath.c
index 75c1ae7..03ee790 100644
--- a/src/fido/oath.c
+++ b/src/fido/oath.c
@@ -158,7 +158,7 @@ int cmd_put() {
     }
     file_t *ef = find_oath_cred(name.data, name.len);
     if (file_has_data(ef)) {
-        flash_write_data_to_file(ef, apdu.data, apdu.nc);
+        file_put_data(ef, apdu.data, apdu.nc);
         low_flash_available();
     }
     else {
@@ -166,7 +166,7 @@ int cmd_put() {
             file_t *ef = search_dynamic_file(EF_OATH_CRED + i);
             if (!file_has_data(ef)) {
                 ef = file_new(EF_OATH_CRED + i);
-                flash_write_data_to_file(ef, apdu.data, apdu.nc);
+                file_put_data(ef, apdu.data, apdu.nc);
                 low_flash_available();
                 return SW_OK();
             }
@@ -247,7 +247,7 @@ int cmd_set_code() {
     }
     random_gen(NULL, challenge, sizeof(challenge));
     file_t *ef = file_new(EF_OATH_CODE);
-    flash_write_data_to_file(ef, key.data, key.len);
+    file_put_data(ef, key.data, key.len);
     low_flash_available();
     validated = false;
     return SW_OK();
@@ -429,7 +429,7 @@ int cmd_calculate() {
         chal.data[5] = v >> 16;
         chal.data[6] = v >> 8;
         chal.data[7] = v & 0xff;
-        flash_write_data_to_file(ef, tmp, ef_size);
+        file_put_data(ef, tmp, ef_size);
         low_flash_available();
         free(tmp);
     }
@@ -504,7 +504,7 @@ int cmd_set_otp_pin() {
     }
     hsh[0] = MAX_OTP_COUNTER;
     double_hash_pin(pw.data, pw.len, hsh + 1);
-    flash_write_data_to_file(ef_otp_pin, hsh, sizeof(hsh));
+    file_put_data(ef_otp_pin, hsh, sizeof(hsh));
     low_flash_available();
     return SW_OK();
 }
@@ -529,7 +529,7 @@ int cmd_change_otp_pin() {
     }
     hsh[0] = MAX_OTP_COUNTER;
     double_hash_pin(new_pw.data, new_pw.len, hsh + 1);
-    flash_write_data_to_file(ef_otp_pin, hsh, sizeof(hsh));
+    file_put_data(ef_otp_pin, hsh, sizeof(hsh));
     low_flash_available();
     return SW_OK();
 }
@@ -551,13 +551,13 @@ int cmd_verify_otp_pin() {
         if (data_hsh[0] > 0) {
             data_hsh[0] -= 1;
         }
-        flash_write_data_to_file(ef_otp_pin, data_hsh, sizeof(data_hsh));
+        file_put_data(ef_otp_pin, data_hsh, sizeof(data_hsh));
         low_flash_available();
         validated = false;
         return SW_SECURITY_STATUS_NOT_SATISFIED();
     }
     data_hsh[0] = MAX_OTP_COUNTER;
-    flash_write_data_to_file(ef_otp_pin, data_hsh, sizeof(data_hsh));
+    file_put_data(ef_otp_pin, data_hsh, sizeof(data_hsh));
     low_flash_available();
     validated = true;
     return SW_OK();
diff --git a/src/fido/otp.c b/src/fido/otp.c
index e37e779..7d5be77 100644
--- a/src/fido/otp.c
+++ b/src/fido/otp.c
@@ -169,7 +169,7 @@ void init_otp() {
                     memcpy(new_data, data, sizeof(new_data));
                     new_data[otp_config_size] = counter >> 8;
                     new_data[otp_config_size + 1] = counter & 0xff;
-                    flash_write_data_to_file(ef, new_data, sizeof(new_data));
+                    file_put_data(ef, new_data, sizeof(new_data));
                 }
             }
         }
@@ -258,7 +258,7 @@ int otp_button_pressed(uint8_t slot) {
             uint8_t new_otp_config[otp_config_size + sizeof(new_chal)];
             memcpy(new_otp_config, otp_config, otp_config_size);
             memcpy(new_otp_config + otp_config_size, new_chal, sizeof(new_chal));
-            flash_write_data_to_file(ef, new_otp_config, sizeof(new_otp_config));
+            file_put_data(ef, new_otp_config, sizeof(new_otp_config));
             low_flash_available();
         }
         if (otp_config->tkt_flags & APPEND_CR) {
@@ -322,7 +322,7 @@ int otp_button_pressed(uint8_t slot) {
             memcpy(new_data, data, sizeof(new_data));
             new_data[otp_config_size] = counter >> 8;
             new_data[otp_config_size + 1] = counter & 0xff;
-            flash_write_data_to_file(ef, new_data, sizeof(new_data));
+            file_put_data(ef, new_data, sizeof(new_data));
             low_flash_available();
         }
     }
@@ -387,7 +387,7 @@ int cmd_otp() {
                     return SW_WRONG_DATA();
                 }
                 memset(apdu.data + otp_config_size, 0, 8); // Add 8 bytes extra
-                flash_write_data_to_file(ef, apdu.data, otp_config_size + 8);
+                file_put_data(ef, apdu.data, otp_config_size + 8);
                 low_flash_available();
                 config_seq++;
                 return otp_status();
@@ -420,7 +420,7 @@ int cmd_otp() {
                                (odata->tkt_flags & TKTFLAG_UPDATE_MASK);
             odata->cfg_flags = (otpc->cfg_flags & ~CFGFLAG_UPDATE_MASK) |
                                (odata->cfg_flags & CFGFLAG_UPDATE_MASK);
-            flash_write_data_to_file(ef, apdu.data, otp_config_size);
+            file_put_data(ef, apdu.data, otp_config_size);
             low_flash_available();
         }
     }
@@ -434,13 +434,13 @@ int cmd_otp() {
             ef1_data = true;
         }
         if (file_has_data(ef2)) {
-            flash_write_data_to_file(ef1, file_get_data(ef2), file_get_size(ef2));
+            file_put_data(ef1, file_get_data(ef2), file_get_size(ef2));
         }
         else {
             delete_file(ef1);
         }
         if (ef1_data) {
-            flash_write_data_to_file(ef2, tmp, sizeof(tmp));
+            file_put_data(ef2, tmp, sizeof(tmp));
         }
         else {
             delete_file(ef2);