diff --git a/comm/messages.c b/comm/messages.c
index 2b4105b..620a17e 100644
--- a/comm/messages.c
+++ b/comm/messages.c
@@ -2,6 +2,7 @@
 // Created by MightyPork on 2017/11/21.
 //
 
+#include <platform/status_led.h>
 #include "platform.h"
 #include "framework/settings.h"
 #include "utils/ini_parser.h"
@@ -91,6 +92,7 @@ static TF_Result lst_ini_export(TinyFrame *tf, TF_Msg *msg)
     bulk->userdata = NULL;
 
     bulkread_start(tf, bulk);
+    Indicator_Effect(STATUS_DISK_BUSY_SHORT);
 
     return TF_STAY;
 }
@@ -152,6 +154,8 @@ static TF_Result lst_ini_import(TinyFrame *tf, TF_Msg *msg)
 
     bulkwrite_start(tf, bulk);
 
+    Indicator_Effect(STATUS_DISK_BUSY);
+
 done:
     return TF_STAY;
 }
@@ -161,6 +165,7 @@ done:
 /** Listener: Save settings to Flash */
 static TF_Result lst_persist_cfg(TinyFrame *tf, TF_Msg *msg)
 {
+    Indicator_Effect(STATUS_DISK_REMOVED);
     settings_save();
     return TF_STAY;
 }
diff --git a/platform/status_led.c b/platform/status_led.c
index cc66f2f..e031965 100644
--- a/platform/status_led.c
+++ b/platform/status_led.c
@@ -61,6 +61,12 @@ void Indicator_Effect(enum GEX_StatusIndicator indicator)
         led_on();
     }
 
+    // prevent the two disk ops interfering (happens in write-reload)
+    if (indicator == STATUS_DISK_BUSY && active_effect == STATUS_DISK_BUSY_SHORT) return;
+    if (indicator == STATUS_DISK_BUSY_SHORT && active_effect == STATUS_DISK_BUSY) return;
+
+    // TODO add some better protection against effect overlap?
+
     active_effect = indicator;
     effect_time = 0;
 }
@@ -119,7 +125,15 @@ void Indicator_Tick(void)
                 active_effect = STATUS_NONE;
             }
             else if (effect_time % 100 == 0) led_on();
-            else if (effect_time % 100 == 50) led_off();
+            else if (effect_time % 100 == 20) led_off();
+        }
+        else if (active_effect == STATUS_DISK_BUSY_SHORT) {
+            if (effect_time >= 200) {
+                led_off();
+                active_effect = STATUS_NONE;
+            }
+            else if (effect_time % 100 == 0) led_on();
+            else if (effect_time % 100 == 20) led_off();
         }
         else if (active_effect == STATUS_WELCOME) {
             if (effect_time == 0) led_on();
diff --git a/platform/status_led.h b/platform/status_led.h
index f61e3a9..5dbeb2d 100644
--- a/platform/status_led.h
+++ b/platform/status_led.h
@@ -16,6 +16,7 @@ enum GEX_StatusIndicator {
     STATUS_NONE = 0,
     STATUS_FAULT,
     STATUS_DISK_BUSY,
+    STATUS_DISK_BUSY_SHORT,
     STATUS_DISK_ATTACHED,
     STATUS_DISK_REMOVED,
     STATUS_WELCOME,
diff --git a/units/touch/_touch_core.c b/units/touch/_touch_core.c
index 8c1cf7b..76f8ebb 100644
--- a/units/touch/_touch_core.c
+++ b/units/touch/_touch_core.c
@@ -30,7 +30,7 @@ void UTOUCH_HandleIrq(void *arg)
 //        assert_param((TSC->IOGCSR>>16) == priv->groups_phase[priv->next_phase]);
 
         // Store captured data
-        const uint32_t chmask = priv->channels_phase[priv->next_phase];
+        const uint32_t chmask = TSC->IOCCR;
         for (int i = 0; i < 32; i++) {
             if (chmask & (1<<i)) {
                 priv->readouts[i] = (uint16_t) (TSC->IOGXCR[i >> 2] & 0x3FFF);
@@ -38,11 +38,14 @@ void UTOUCH_HandleIrq(void *arg)
         }
 
         priv->next_phase++;
-        // check if we've run out of existing or populated groups
-        if (priv->next_phase == 3 || priv->groups_phase[priv->next_phase] == 0) {
-            priv->next_phase = 0;
-            priv->status = UTSC_STATUS_READY;
-            // we'll stay in READY after the first loop until an error occurs or it's re-inited
+
+        if (!priv->cfg.interlaced) {
+            // check if we've run out of existing or populated groups
+            if (priv->next_phase == 3 || priv->groups_phase[priv->next_phase] == 0) {
+                priv->next_phase = 0;
+                priv->status = UTSC_STATUS_READY;
+                // we'll stay in READY after the first loop until an error occurs or it's re-inited
+            }
         }
 
         TSC->CR &= ~TSC_CR_IODEF; // pull low - discharge
@@ -90,21 +93,31 @@ void UTOUCH_updateTick(Unit *unit)
 
 static void startNextPhase(struct priv *priv)
 {
-    if (priv->next_phase == 0 && priv->groups_phase[0] == 0) {
-        // no groups are configured
-        return;
-    }
-
-    TSC->IOGCSR = priv->groups_phase[priv->next_phase];
-    TSC->IOCCR = priv->channels_phase[priv->next_phase];
-    TSC->ICR = TSC_ICR_EOAIC | TSC_ICR_MCEIC;
+    if (priv->all_channels_mask == 0) return;
 
     if (priv->cfg.interlaced) {
+        // Find the next non-zero bit, wrap around if needed
+        while ((priv->all_channels_mask & (1<<priv->next_phase))==0) {
+            priv->next_phase++;
+            if (priv->next_phase == 32) {
+                priv->next_phase = 0;
+                priv->status = UTSC_STATUS_READY;
+            }
+        }
+        TSC->IOGCSR = (uint32_t) (1 << (priv->next_phase >> 2)); // phase divided by 4
+        TSC->IOCCR = (uint32_t) (1 << priv->next_phase);
+
+        // interlaced - float neighbouring electrodes
         TSC->CR |= TSC_CR_IODEF;
-        // floaty (must be used for interlaced pads)
-        // note: interlaced pads also need to be sampled individually
+    } else {
+        TSC->IOGCSR = priv->groups_phase[priv->next_phase];
+        TSC->IOCCR = priv->channels_phase[priv->next_phase];
+
+        // separate - keep neighbouring electrodes at GND
     }
 
+    TSC->ICR = TSC_ICR_EOAIC | TSC_ICR_MCEIC;
+
     // Go!
     priv->ongoing = true;
     TSC->CR |= TSC_CR_START;
diff --git a/units/touch/_touch_init.c b/units/touch/_touch_init.c
index 965d227..4321b4f 100644
--- a/units/touch/_touch_init.c
+++ b/units/touch/_touch_init.c
@@ -75,6 +75,8 @@ error_t UTOUCH_init(Unit *unit)
     __HAL_RCC_TSC_FORCE_RESET();
     __HAL_RCC_TSC_RELEASE_RESET();
 
+    priv->all_channels_mask = 0;
+
     for (int gi = 0; gi < 8; gi++) {
         const uint8_t cap = priv->cfg.group_scaps[gi];
         const uint8_t ch = priv->cfg.group_channels[gi];
@@ -132,11 +134,16 @@ error_t UTOUCH_init(Unit *unit)
             else {
                 dbg_touch("TSC ch @ %s", rsc_get_name(r));
 
-                // channels are configured individually when read.
-                // we prepare bitmaps to use for the read groups (all can be read in at most 3 steps)
-                priv->channels_phase[phasenum] |= bit; // this is used for the channel selection register
-                priv->groups_phase[phasenum] |= 1 << gi; // this will be used for the group enable register, if all 0, this and any following phases are unused.
-                phasenum++;
+                if (priv->cfg.interlaced) {
+                    // interlaced - only update the mask beforehand
+                    priv->all_channels_mask |= bit;
+                } else {
+                    // channels are configured individually when read.
+                    // we prepare bitmaps to use for the read groups (all can be read in at most 3 steps)
+                    priv->channels_phase[phasenum] |= bit; // this is used for the channel selection register
+                    priv->groups_phase[phasenum] |= 1 << gi; // this will be used for the group enable register, if all 0, this and any following phases are unused.
+                    phasenum++;
+                }
             }
         }
     }
@@ -154,7 +161,9 @@ error_t UTOUCH_init(Unit *unit)
         TSC->CR |= ((priv->cfg.spread_deviation - 1) << TSC_CR_SSD_Pos) | TSC_CR_SSE;
     }
 
-    dbg_touch("CR = %08x, ht is %d, lt is %d", TSC->CR, priv->cfg.charge_time, priv->cfg.drain_time);
+    dbg_touch("CR = %08x, ht is %d, lt is %d", (int)TSC->CR,
+              (int)priv->cfg.charge_time,
+              (int)priv->cfg.drain_time);
 
     // iofloat is used for discharging
 
@@ -162,16 +171,22 @@ error_t UTOUCH_init(Unit *unit)
     TSC->IER = TSC_IER_EOAIE | TSC_IER_MCEIE;
     irqd_attach(TSC, UTOUCH_HandleIrq, unit);
 
-    dbg_touch("TSC phases:");
-    priv->all_channels_mask = 0;
-    for (int i = 0; i < 3; i++) {
-        priv->all_channels_mask |= priv->channels_phase[i];
-        dbg_touch(" %d: ch %08"PRIx32", g %02"PRIx32, i + 1, priv->channels_phase[i], (uint32_t) priv->groups_phase[i]);
+    if (!priv->cfg.interlaced) {
+        dbg_touch("TSC phases:");
+        for (int i = 0; i < 3; i++) {
+            priv->all_channels_mask |= priv->channels_phase[i];
+
+            dbg_touch(" %d: ch %08"PRIx32", g %02"PRIx32,
+                      i + 1,
+                      priv->channels_phase[i],
+                      (uint32_t) priv->groups_phase[i]);
+        }
     }
 
     priv->status = UTSC_STATUS_BUSY; // first loop ...
     priv->next_phase = 0;
-    UTOUCH_updateTick(unit);
+
+    // starts in the tick callback
 
     return E_SUCCESS;
 }
diff --git a/units/touch/_touch_internal.h b/units/touch/_touch_internal.h
index 056fe11..ffc6d39 100644
--- a/units/touch/_touch_internal.h
+++ b/units/touch/_touch_internal.h
@@ -11,7 +11,7 @@
 
 #include "unit_base.h"
 
-#define TSC_DEBUG 1
+#define TSC_DEBUG 0
 
 #if TSC_DEBUG
 #define dbg_touch(f,...) dbg(f,##__VA_ARGS__)
diff --git a/units/touch/_touch_settings.c b/units/touch/_touch_settings.c
index 3340c06..9c2b244 100644
--- a/units/touch/_touch_settings.c
+++ b/units/touch/_touch_settings.c
@@ -149,7 +149,7 @@ void UTOUCH_writeIni(Unit *unit, IniWriter *iw)
     iw_entry(iw, "ss-clock-prediv", "%d", (int)priv->cfg.ss_presc);
 
     iw_cmt_newline(iw);
-    iw_comment(iw, "Optimize for interlaced pads");
+    iw_comment(iw, "Optimize for interlaced pads (individual sampling with others floating)");
     iw_entry(iw, "interlaced-pads", str_yn(priv->cfg.interlaced));
 
     iw_cmt_newline(iw);