diff --git a/ccid_common/ccid_slot_fsm.c b/ccid_common/ccid_slot_fsm.c
index a7ecb9f..870cf35 100644
--- a/ccid_common/ccid_slot_fsm.c
+++ b/ccid_common/ccid_slot_fsm.c
@@ -31,12 +31,18 @@
 
 static struct iso_fsm_slot_instance g_si;
 
-struct iso_fsm_slot *ccid_slot2iso_fsm_slot(struct ccid_slot *cs)
+static struct iso_fsm_slot *ccid_slot2iso_fsm_slot(struct ccid_slot *cs)
 {
 	OSMO_ASSERT(cs->slot_nr < ARRAY_SIZE(g_si.slot));
 	return &g_si.slot[cs->slot_nr];
 }
 
+struct card_uart *cuart4slot_nr(uint8_t slot_nr)
+{
+	OSMO_ASSERT(slot_nr < ARRAY_SIZE(g_si.slot));
+	return g_si.slot[slot_nr].cuart;
+}
+
 static const uint8_t sysmousim_sjs1_atr[] = {
 		0x3B, 0x9F, 0x96, 0x80, 0x1F, 0xC7, 0x80, 0x31,
 		0xA0, 0x73, 0xBE, 0x21, 0x13, 0x67, 0x43, 0x20,
@@ -74,9 +80,10 @@
 	osmo_fsm_inst_dispatch(ss->fi, ISO7816_E_POWER_UP_IND, NULL);
 	cs->icc_powered = true;
 	card_uart_ctrl(ss->cuart, CUART_CTL_CLOCK, true);
-	usleep(10000);
-	card_uart_ctrl(ss->cuart, CUART_CTL_RST, false);
+	delay_us(10000);
+
 	osmo_fsm_inst_dispatch(ss->fi, ISO7816_E_RESET_REL_IND, NULL);
+	card_uart_ctrl(ss->cuart, CUART_CTL_RST, false);
 
 	msgb_free(msg);
 	/* continues in iso_fsm_clot_user_cb once ATR is received */
@@ -145,8 +152,10 @@
 
 	if (enable) {
 		card_uart_ctrl(ss->cuart, CUART_CTL_POWER, true);
+		cs->icc_powered = true;
 	} else {
 		card_uart_ctrl(ss->cuart, CUART_CTL_POWER, false);
+		cs->icc_powered = false;
 	}
 }
 
@@ -179,31 +188,35 @@
 	return 0;
 }
 
-
+extern void *g_tall_ctx;
 static int iso_fsm_slot_init(struct ccid_slot *cs)
 {
-	void *ctx = NULL; /* FIXME */
+	void *ctx = g_tall_ctx; /* FIXME */
 	struct iso_fsm_slot *ss = ccid_slot2iso_fsm_slot(cs);
 	struct card_uart *cuart = talloc_zero(ctx, struct card_uart);
-	char id_buf[16];
-	char *devname = NULL;
+	char id_buf[16] = "SIM0";
+	char devname[] = "foobar";
 	int rc;
 
 	LOGPCS(cs, LOGL_DEBUG, "%s\n", __func__);
 
 	/* HACK: make this in some way configurable so it works both in the firmware
 	 * and on the host (functionfs) */
-	if (cs->slot_nr == 0) {
-		cs->icc_present = true;
-		devname = "/dev/ttyUSB5";
-	}
+//	if (cs->slot_nr == 0) {
+//		cs->icc_present = true;
+//		devname = "/dev/ttyUSB5";
+//	}
+	devname[0] = cs->slot_nr +0x30;
+	devname[1] = 0;
+	//sprintf(devname, "%d", cs->slot_nr);
 
 	if (!cuart)
 		return -ENOMEM;
 
-	snprintf(id_buf, sizeof(id_buf), "SIM%d", cs->slot_nr);
+	//snprintf(id_buf, sizeof(id_buf), "SIM%d", cs->slot_nr);
+	id_buf[3] = cs->slot_nr +0x30;
 	if (devname) {
-		rc = card_uart_open(cuart, "tty", devname);
+		rc = card_uart_open(cuart, "asf4", devname);
 		if (rc < 0) {
 			LOGPCS(cs, LOGL_ERROR, "Cannot open UART %s: %d\n", devname, rc);
 			talloc_free(cuart);
diff --git a/ccid_common/cuart.h b/ccid_common/cuart.h
index 951a3ec..5e397ab 100644
--- a/ccid_common/cuart.h
+++ b/ccid_common/cuart.h
@@ -7,6 +7,8 @@
 #include <osmocom/core/select.h>
 #include "utils_ringbuffer.h"
 
+struct usart_async_descriptor;
+
 enum card_uart_event {
 	/* a single byte was received, it's present at the (uint8_t *) data location */
 	CUART_E_RX_SINGLE,
@@ -90,6 +92,10 @@
 			struct osmo_fd ofd;
 			unsigned int baudrate;
 		} tty;
+		struct {
+			struct usart_async_descriptor *usa_pd;
+			uint8_t slot_nr;
+		} asf4;
 	} u;
 };
 
diff --git a/ccid_host/ccid_slot_sim.c b/ccid_host/ccid_slot_sim.c
index 1bd514a..dc33114 100644
--- a/ccid_host/ccid_slot_sim.c
+++ b/ccid_host/ccid_slot_sim.c
@@ -100,9 +100,10 @@
 {
 	if (enable) {
 		cs->icc_powered = true;
-		/* FIXME: What to do about ATR? */
+		cs->icc_in_reset = false;
 	} else {
 		cs->icc_powered = false;
+		cs->icc_in_reset = true;
 	}
 }
 
diff --git a/sysmoOCTSIM/cuart_driver_asf4_usart_async.c b/sysmoOCTSIM/cuart_driver_asf4_usart_async.c
new file mode 100644
index 0000000..f9856f3
--- /dev/null
+++ b/sysmoOCTSIM/cuart_driver_asf4_usart_async.c
@@ -0,0 +1,402 @@
+/* Card (ICC) UART driver for the Atmel ASF4 asynchronous USART */
+
+#include <errno.h>
+
+#include <osmocom/core/linuxlist.h>
+#include <osmocom/core/utils.h>
+
+#include <hal_usart_async.h>
+#include <utils_ringbuffer.h>
+#include "driver_init.h"
+
+#include "ncn8025.h"
+
+#include "cuart.h"
+
+static struct usart_async_descriptor* SIM_peripheral_descriptors[] = {&SIM0, &SIM1, &SIM2, &SIM3, &SIM4, &SIM5, &SIM6, NULL};
+
+extern struct card_uart *cuart4slot_nr(uint8_t slot_nr);
+
+/***********************************************************************
+ * low-level helper routines
+ ***********************************************************************/
+
+static void _SIM_rx_cb(const struct usart_async_descriptor *const io_descr, uint8_t slot_nr)
+{
+	struct card_uart *cuart = cuart4slot_nr(slot_nr);
+	int rc;
+	OSMO_ASSERT(cuart);
+
+	if (cuart->rx_threshold == 1) {
+		/* bypass ringbuffer and report byte directly */
+		uint8_t rx[1];
+		rc = io_read((struct io_descriptor * const)&io_descr->io, rx, sizeof(rx));
+		OSMO_ASSERT(rc == sizeof(rx));
+		card_uart_notification(cuart, CUART_E_RX_SINGLE, rx);
+	} else {
+		/* go via ringbuffer and notify only after threshold */
+		if (ringbuffer_num(&io_descr->rx) >= cuart->rx_threshold)
+			card_uart_notification(cuart, CUART_E_RX_COMPLETE, NULL);
+	}
+}
+
+static void _SIM_tx_cb(const struct usart_async_descriptor *const io_descr, uint8_t slot_nr)
+{
+	struct card_uart *cuart = cuart4slot_nr(slot_nr);
+	OSMO_ASSERT(cuart);
+	card_uart_notification(cuart, CUART_E_TX_COMPLETE, io_descr->tx_buffer);
+}
+
+#include <hpl_usart_async.h>
+#include <hpl_usart_sync.h>
+
+
+static void _SIM_error_cb(const struct usart_async_descriptor *const descr){
+	volatile uint32_t status = hri_sercomusart_read_STATUS_reg(descr->device.hw);
+	volatile uint32_t data = hri_sercomusart_read_DATA_reg(descr->device.hw);
+	volatile uint32_t errrs = hri_sercomusart_read_RXERRCNT_reg(descr->device.hw);
+	OSMO_ASSERT(0 == 1)
+}
+
+/* the below ugli-ness is required as the usart_async_descriptor doesn't have
+ * some kind of 'private' member that could provide the call-back anty kind of
+ * context */
+static void SIM0_rx_cb(const struct usart_async_descriptor *const io_descr)
+{
+	_SIM_rx_cb(io_descr, 0);
+}
+static void SIM1_rx_cb(const struct usart_async_descriptor *const io_descr)
+{
+	_SIM_rx_cb(io_descr, 1);
+}
+static void SIM2_rx_cb(const struct usart_async_descriptor *const io_descr)
+{
+	_SIM_rx_cb(io_descr, 2);
+}
+static void SIM3_rx_cb(const struct usart_async_descriptor *const io_descr)
+{
+	_SIM_rx_cb(io_descr, 3);
+}
+static void SIM4_rx_cb(const struct usart_async_descriptor *const io_descr)
+{
+	_SIM_rx_cb(io_descr, 4);
+}
+static void SIM5_rx_cb(const struct usart_async_descriptor *const io_descr)
+{
+	_SIM_rx_cb(io_descr, 5);
+}
+static void SIM6_rx_cb(const struct usart_async_descriptor *const io_descr)
+{
+	_SIM_rx_cb(io_descr, 6);
+}
+static void SIM7_rx_cb(const struct usart_async_descriptor *const io_descr)
+{
+	_SIM_rx_cb(io_descr, 7);
+}
+static usart_cb_t SIM_rx_cb[8] = {
+	SIM0_rx_cb, SIM1_rx_cb, SIM2_rx_cb, SIM3_rx_cb,
+	SIM4_rx_cb, SIM5_rx_cb, SIM6_rx_cb, SIM7_rx_cb,
+};
+static void SIM0_tx_cb(const struct usart_async_descriptor *const io_descr)
+{
+	_SIM_tx_cb(io_descr, 0);
+}
+static void SIM1_tx_cb(const struct usart_async_descriptor *const io_descr)
+{
+	_SIM_tx_cb(io_descr, 1);
+}
+static void SIM2_tx_cb(const struct usart_async_descriptor *const io_descr)
+{
+	_SIM_tx_cb(io_descr, 2);
+}
+static void SIM3_tx_cb(const struct usart_async_descriptor *const io_descr)
+{
+	_SIM_tx_cb(io_descr, 3);
+}
+static void SIM4_tx_cb(const struct usart_async_descriptor *const io_descr)
+{
+	_SIM_tx_cb(io_descr, 4);
+}
+static void SIM5_tx_cb(const struct usart_async_descriptor *const io_descr)
+{
+	_SIM_tx_cb(io_descr, 5);
+}
+static void SIM6_tx_cb(const struct usart_async_descriptor *const io_descr)
+{
+	_SIM_tx_cb(io_descr, 6);
+}
+static void SIM7_tx_cb(const struct usart_async_descriptor *const io_descr)
+{
+	_SIM_tx_cb(io_descr, 7);
+}
+static usart_cb_t SIM_tx_cb[8] = {
+	SIM0_tx_cb, SIM1_tx_cb, SIM2_tx_cb, SIM3_tx_cb,
+	SIM4_tx_cb, SIM5_tx_cb, SIM6_tx_cb, SIM7_tx_cb,
+};
+
+#include <math.h>
+#include "atmel_start.h"
+#include "atmel_start_pins.h"
+#include "config/hpl_gclk_config.h"
+#include "iso7816_3.h"
+
+/** possible clock sources for the SERCOM peripheral
+ *  warning: the definition must match the GCLK configuration
+ */
+static const uint8_t sercom_glck_sources[] = {GCLK_PCHCTRL_GEN_GCLK2_Val, GCLK_PCHCTRL_GEN_GCLK4_Val, GCLK_PCHCTRL_GEN_GCLK6_Val};
+
+ /** possible clock frequencies in MHz for the SERCOM peripheral
+  *  warning: the definition must match the GCLK configuration
+  */
+static const double sercom_glck_freqs[] = {100E6 / CONF_GCLK_GEN_2_DIV, 100E6 / CONF_GCLK_GEN_4_DIV, 120E6 / CONF_GCLK_GEN_6_DIV};
+
+/** the GCLK ID for the SERCOM SIM peripherals
+ *  @note: used as index for PCHCTRL
+ */
+static const uint8_t SIM_peripheral_GCLK_ID[] = {SERCOM0_GCLK_ID_CORE, SERCOM1_GCLK_ID_CORE, SERCOM2_GCLK_ID_CORE, SERCOM3_GCLK_ID_CORE, SERCOM4_GCLK_ID_CORE, SERCOM5_GCLK_ID_CORE, SERCOM6_GCLK_ID_CORE, SERCOM7_GCLK_ID_CORE};
+
+
+/** change baud rate of card slot
+ *  @param[in] slotnr slot number for which the baud rate should be set
+ *  @param[in] baudrate baud rate in bps to set
+ *  @return if the baud rate has been set, else a parameter is out of range
+ */
+static bool slot_set_baudrate(uint8_t slotnr, uint32_t baudrate)
+{
+	ASSERT(slotnr < ARRAY_SIZE(SIM_peripheral_descriptors));
+
+	// calculate the error corresponding to the clock sources
+	uint16_t bauds[ARRAY_SIZE(sercom_glck_freqs)];
+	double errors[ARRAY_SIZE(sercom_glck_freqs)];
+	for (uint8_t i = 0; i < ARRAY_SIZE(sercom_glck_freqs); i++) {
+		double freq = sercom_glck_freqs[i]; // remember possible SERCOM frequency
+		uint32_t min = freq/16. *  (1. - 65535. / 65536.); // calculate the minimum baud rate for this frequency
+		uint32_t max = freq/16. *  (1. - 1. / 65536.); // calculate the maximum baud rate for this frequency
+		if (baudrate < min || baudrate > max) { // baud rate it out of supported range
+			errors[i] = NAN;
+		} else {
+			uint16_t baud = round(65536. * (1. - 16. * (baudrate/freq)));
+			bauds[i] = baud;
+			double actual = freq/16. *  (1. - baud / 65536.);
+			errors[i] = fabs(1.0 - (actual / baudrate));
+		}
+	}
+
+	// find the smallest error
+	uint8_t best = ARRAY_SIZE(sercom_glck_freqs);
+	for (uint8_t i = 0; i < ARRAY_SIZE(sercom_glck_freqs); i++) {
+		if (isnan(errors[i])) {
+			continue;
+		}
+		if (best >= ARRAY_SIZE(sercom_glck_freqs)) {
+			best = i;
+		} else if (errors[i] < errors[best]) {
+			best = i;
+		}
+	}
+	if (best >= ARRAY_SIZE(sercom_glck_freqs)) { // found no clock supporting this baud rate
+		return false;
+	}
+
+	// set clock and baud rate
+	struct usart_async_descriptor* slot = SIM_peripheral_descriptors[slotnr]; // get slot
+	if (NULL == slot) {
+		return false;
+	}
+	printf("(%u) switching SERCOM clock to GCLK%u (freq = %lu kHz) and baud rate to %lu bps (baud = %u)\r\n", slotnr, (best + 1) * 2, (uint32_t)(round(sercom_glck_freqs[best] / 1000)), baudrate, bauds[best]);
+	while (!usart_async_is_tx_empty(slot)); // wait for transmission to complete (WARNING no timeout)
+	usart_async_disable(slot); // disable SERCOM peripheral
+	hri_gclk_clear_PCHCTRL_reg(GCLK, SIM_peripheral_GCLK_ID[slotnr], (1 << GCLK_PCHCTRL_CHEN_Pos)); // disable clock for this peripheral
+	while (hri_gclk_get_PCHCTRL_reg(GCLK, SIM_peripheral_GCLK_ID[slotnr], (1 << GCLK_PCHCTRL_CHEN_Pos))); // wait until clock is really disabled
+	// it does not seem we need to completely disable the peripheral using hri_mclk_clear_APBDMASK_SERCOMn_bit
+	hri_gclk_write_PCHCTRL_reg(GCLK, SIM_peripheral_GCLK_ID[slotnr], sercom_glck_sources[best] | (1 << GCLK_PCHCTRL_CHEN_Pos)); // set peripheral core clock and re-enable it
+	usart_async_set_baud_rate(slot, bauds[best]); // set the new baud rate
+	usart_async_enable(slot); // re-enable SERCOM peripheral
+
+	return true;
+}
+
+/** change ISO baud rate of card slot
+ *  @param[in] slotnr slot number for which the baud rate should be set
+ *  @param[in] clkdiv can clock divider
+ *  @param[in] f clock rate conversion integer F
+ *  @param[in] d baud rate adjustment factor D
+ *  @return if the baud rate has been set, else a parameter is out of range
+ */
+static bool slot_set_isorate(uint8_t slotnr, enum ncn8025_sim_clkdiv clkdiv, uint16_t f, uint8_t d)
+{
+	// input checks
+	ASSERT(slotnr < ARRAY_SIZE(SIM_peripheral_descriptors));
+	if (clkdiv != SIM_CLKDIV_1 && clkdiv != SIM_CLKDIV_2 && clkdiv != SIM_CLKDIV_4 && clkdiv != SIM_CLKDIV_8) {
+		return false;
+	}
+	if (!iso7816_3_valid_f(f)) {
+		return false;
+	}
+	if (!iso7816_3_valid_d(d)) {
+		return false;
+	}
+
+	// set clockdiv
+	struct ncn8025_settings settings;
+	ncn8025_get(slotnr, &settings);
+	if (settings.clkdiv != clkdiv) {
+		settings.clkdiv = clkdiv;
+		ncn8025_set(slotnr, &settings);
+	}
+
+	// calculate desired frequency
+	uint32_t freq = 20000000UL; // maximum frequency
+	switch (clkdiv) {
+	case SIM_CLKDIV_1:
+		freq /= 1;
+		break;
+	case SIM_CLKDIV_2:
+		freq /= 2;
+		break;
+	case SIM_CLKDIV_4:
+		freq /= 4;
+		break;
+	case SIM_CLKDIV_8:
+		freq /= 8;
+		break;
+	}
+
+	// set baud rate
+	uint32_t baudrate = (freq * d) / f; // calculate actual baud rate
+	return slot_set_baudrate(slotnr, baudrate); // set baud rate
+}
+
+/***********************************************************************
+ * Interface with card_uart (cuart) core
+ ***********************************************************************/
+
+/* forward-declaration */
+static struct card_uart_driver asf4_usart_driver;
+static int asf4_usart_close(struct card_uart *cuart);
+
+static int asf4_usart_open(struct card_uart *cuart, const char *device_name)
+{
+	struct usart_async_descriptor *usa_pd;
+	int slot_nr = atoi(device_name);
+
+	if (slot_nr >= ARRAY_SIZE(SIM_peripheral_descriptors))
+		return -ENODEV;
+	usa_pd = SIM_peripheral_descriptors[slot_nr];
+	if (!usa_pd)
+		return -ENODEV;
+
+	cuart->u.asf4.usa_pd = usa_pd;
+	cuart->u.asf4.slot_nr = slot_nr;
+
+
+	usart_async_register_callback(usa_pd, USART_ASYNC_RXC_CB, SIM_rx_cb[slot_nr]);
+	usart_async_register_callback(usa_pd, USART_ASYNC_TXC_CB, SIM_tx_cb[slot_nr]);
+	usart_async_register_callback(usa_pd, USART_ASYNC_ERROR_CB, _SIM_error_cb);
+	usart_async_enable(usa_pd);
+
+	// set USART baud rate to match the interface (f = 2.5 MHz) and card default settings (Fd = 372, Dd = 1)
+	slot_set_isorate(cuart->u.asf4.slot_nr, SIM_CLKDIV_8, ISO7816_3_DEFAULT_FD, ISO7816_3_DEFAULT_DD);
+
+        return 0;
+}
+
+static int asf4_usart_close(struct card_uart *cuart)
+{
+	struct usart_async_descriptor *usa_pd = cuart->u.asf4.usa_pd;
+
+	OSMO_ASSERT(cuart->driver == &asf4_usart_driver);
+
+	usart_async_disable(usa_pd);
+
+	return 0;
+}
+
+static int asf4_usart_async_tx(struct card_uart *cuart, const uint8_t *data, size_t len)
+{
+	struct usart_async_descriptor *usa_pd = cuart->u.asf4.usa_pd;
+	int rc;
+
+	OSMO_ASSERT(cuart->driver == &asf4_usart_driver);
+	OSMO_ASSERT(usart_async_is_tx_empty(usa_pd));
+
+	rc = io_write(&usa_pd->io, data, len);
+	if (rc < 0)
+		return rc;
+
+	cuart->tx_busy = true;
+
+	return rc;
+}
+
+static int asf4_usart_async_rx(struct card_uart *cuart, uint8_t *data, size_t len)
+{
+	struct usart_async_descriptor *usa_pd = cuart->u.asf4.usa_pd;
+
+	OSMO_ASSERT(cuart->driver == &asf4_usart_driver);
+
+	return io_read(&usa_pd->io, data, len);
+}
+
+static int asf4_usart_ctrl(struct card_uart *cuart, enum card_uart_ctl ctl, int arg)
+{
+	struct ncn8025_settings settings;
+	Sercom *sercom = cuart->u.asf4.usa_pd->device.hw;
+
+	switch (ctl) {
+	case CUART_CTL_RX:
+		if (arg){
+			sercom->USART.CTRLB.bit.RXEN = 1;
+			sercom->USART.CTRLB.bit.TXEN = 0;
+		} else {
+			delay_us(100);
+			sercom->USART.CTRLB.bit.RXEN = 0;
+			sercom->USART.CTRLB.bit.TXEN = 1;
+		}
+		break;
+	case CUART_CTL_RST:
+		ncn8025_get(cuart->u.asf4.slot_nr, &settings);
+		settings.rstin = arg ? true : false;
+		ncn8025_set(cuart->u.asf4.slot_nr, &settings);
+		usart_async_flush_rx_buffer(cuart->u.asf4.usa_pd);
+		break;
+	case CUART_CTL_POWER:
+		ncn8025_get(cuart->u.asf4.slot_nr, &settings);
+		settings.cmdvcc = arg ? true : false;
+		settings.led = arg ? true : false;
+		settings.vsel = SIM_VOLT_5V0;
+
+		// set USART baud rate to match the interface (f = 2.5 MHz) and card default settings (Fd = 372, Dd = 1)
+		if(arg)
+			slot_set_isorate(cuart->u.asf4.slot_nr, SIM_CLKDIV_8, ISO7816_3_DEFAULT_FD, ISO7816_3_DEFAULT_DD);
+
+		ncn8025_set(cuart->u.asf4.slot_nr, &settings);
+		break;
+	case CUART_CTL_WTIME:
+		/* no driver-specific handling of this */
+		break;
+	case CUART_CTL_CLOCK:
+		/* FIXME */
+	default:
+		return -EINVAL;
+	}
+	return 0;
+}
+
+static const struct card_uart_ops asf4_usart_ops = {
+	.open = asf4_usart_open,
+	.close = asf4_usart_close,
+	.async_tx = asf4_usart_async_tx,
+	.async_rx = asf4_usart_async_rx,
+	.ctrl = asf4_usart_ctrl,
+};
+
+static struct card_uart_driver asf4_usart_driver = {
+	.name = "asf4",
+	.ops = &asf4_usart_ops,
+};
+
+static __attribute__((constructor)) void on_dso_load_cuart_asf4(void)
+{
+	card_uart_driver_register(&asf4_usart_driver);
+}
diff --git a/sysmoOCTSIM/gcc/Makefile b/sysmoOCTSIM/gcc/Makefile
index 595fd62..4840fea 100644
--- a/sysmoOCTSIM/gcc/Makefile
+++ b/sysmoOCTSIM/gcc/Makefile
@@ -83,6 +83,10 @@
 	atmel_start.o \
 	ccid_common/ccid_proto.o \
 	ccid_common/ccid_device.o \
+	ccid_common/iso7816_fsm.o \
+	ccid_common/cuart.o \
+	ccid_common/ccid_slot_fsm.o \
+	cuart_driver_asf4_usart_async.o \
 	command.o \
 	dma_m2m/dma_memory.o \
 	driver_init.o \
diff --git a/sysmoOCTSIM/main.c b/sysmoOCTSIM/main.c
index fed562b..059c99d 100644
--- a/sysmoOCTSIM/main.c
+++ b/sysmoOCTSIM/main.c
@@ -40,48 +40,11 @@
 
 #include "command.h"
 
-// TODO put declaration in more global file
-// TODO for now SIM7 is not present because used for debug
-static struct usart_async_descriptor* SIM_peripheral_descriptors[] = {&SIM0, &SIM1, &SIM2, &SIM3, &SIM4, &SIM5, &SIM6, NULL};
 #include "ccid_device.h"
 #include "usb_descriptors.h"
+extern struct ccid_slot_ops iso_fsm_slot_ops;
+static struct ccid_instance g_ci;
 
-/** number of bytes transmitted on the SIM peripheral */
-static volatile bool SIM_tx_count[8];
-
-static void SIM_rx_cb(const struct usart_async_descriptor *const io_descr)
-{
-}
-
-/** called when the transmission is complete
- *  e.g. this is when the byte has been sent and there is no data to transmit anymore
- */
-static void SIM_tx_cb(const struct usart_async_descriptor *const io_descr)
-{
-	// find slotnr for corresponding USART
-	uint8_t slotnr;
-	for (slotnr = 0; slotnr < ARRAY_SIZE(SIM_peripheral_descriptors) && SIM_peripheral_descriptors[slotnr] != io_descr; slotnr++);
-
-	// set flag
-	if (slotnr < ARRAY_SIZE(SIM_peripheral_descriptors)) {
-		SIM_tx_count[slotnr] = true;
-	}
-}
-
-/** possible clock sources for the SERCOM peripheral
- *  warning: the definition must match the GCLK configuration
- */
-static const uint8_t sercom_glck_sources[] = {GCLK_PCHCTRL_GEN_GCLK2_Val, GCLK_PCHCTRL_GEN_GCLK4_Val, GCLK_PCHCTRL_GEN_GCLK6_Val};
-
-/** possible clock frequencies in MHz for the SERCOM peripheral
- *  warning: the definition must match the GCLK configuration
- */
-static const double sercom_glck_freqs[] = {100E6 / CONF_GCLK_GEN_2_DIV, 100E6 / CONF_GCLK_GEN_4_DIV, 120E6 / CONF_GCLK_GEN_6_DIV};
-
-/** the GCLK ID for the SERCOM SIM peripherals
- *  @note: used as index for PCHCTRL
- */
-static const uint8_t SIM_peripheral_GCLK_ID[] = {SERCOM0_GCLK_ID_CORE, SERCOM1_GCLK_ID_CORE, SERCOM2_GCLK_ID_CORE, SERCOM3_GCLK_ID_CORE, SERCOM4_GCLK_ID_CORE, SERCOM5_GCLK_ID_CORE, SERCOM6_GCLK_ID_CORE, SERCOM7_GCLK_ID_CORE};
 
 static void ccid_app_init(void);
 
@@ -103,16 +66,6 @@
 	 * (there are 8 inputs + traces to drive!) */
 	hri_port_set_PINCFG_DRVSTR_bit(PORT, 0, 11);
 
-	// enable SIM interfaces
-	for (uint8_t i = 0; i < ARRAY_SIZE(SIM_peripheral_descriptors); i++) {
-		if (NULL == SIM_peripheral_descriptors[i]) {
-			continue;
-		}
-		usart_async_register_callback(SIM_peripheral_descriptors[i], USART_ASYNC_RXC_CB, SIM_rx_cb); // required for RX to work, even if the callback does nothing
-		usart_async_register_callback(SIM_peripheral_descriptors[i], USART_ASYNC_TXC_CB, SIM_tx_cb); // to count the number of bytes transmitted since we are using it asynchronously
-		usart_async_enable(SIM_peripheral_descriptors[i]);
-	}
-
 	ccid_app_init();
 }
 
@@ -201,7 +154,9 @@
 	struct msgb *msg;
 	int rc;
 
-	OSMO_ASSERT(!ep_q->in_progress);
+	if (ep_q->in_progress)
+		return 0;
+
 	msg = msgb_dequeue_irqsafe(&ep_q->list);
 	if (!msg)
 		return 0;
@@ -250,6 +205,7 @@
 	msg = msgb_dequeue_irqsafe(&g_ccid_s.free_q);
 	if (!msg)
 		return -1;
+	msgb_reset(msg);
 	ep_q->in_progress = msg;
 
 	rc = ccid_df_read_out(msgb_data(msg), msgb_tailroom(msg));
@@ -272,6 +228,7 @@
 	msgb_put(msg, transferred);
 	/* append to list of pending-to-be-handed messages */
 	llist_add_tail_at(&msg->list, &g_ccid_s.out_ep.list);
+	g_ccid_s.out_ep.in_progress = NULL;
 
 	/* submit another [free] msgb to receive the next transfer */
 	submit_next_out();
@@ -343,8 +300,11 @@
 	struct msgb *msg;
 	unsigned int i;
 
-	for (i = 0; i < 8; i++)
-		new_mask |= ncn8025_interrupt_level(i) << i;
+	for (i = 0; i < 8; i++){
+		bool level = ncn8025_interrupt_level(i);
+		new_mask |= level << i;
+		g_ci.slot[i].icc_present = level;
+	}
 
 	/* notify the user/host about any changes */
 	if (g_ccid_s.card_insert_mask != new_mask) {
@@ -363,629 +323,6 @@
  * Command Line interface
  ***********************************************************************/
 
-static int validate_slotnr(int argc, char **argv, int idx)
-{
-	int slotnr;
-	if (argc < idx+1) {
-		printf("You have to specify the slot number (0..7)\r\n");
-		return -1;
-	}
-	slotnr = atoi(argv[idx]);
-	if (slotnr < 0 || slotnr > 7) {
-		printf("You have to specify the slot number (0..7)\r\n");
-		return -1;
-	}
-	return slotnr;
-}
-
-/** change baud rate of card slot
- *  @param[in] slotnr slot number for which the baud rate should be set
- *  @param[in] baudrate baud rate in bps to set
- *  @return if the baud rate has been set, else a parameter is out of range
- */
-static bool slot_set_baudrate(uint8_t slotnr, uint32_t baudrate)
-{
-	ASSERT(slotnr < ARRAY_SIZE(SIM_peripheral_descriptors));
-
-	// calculate the error corresponding to the clock sources
-	uint16_t bauds[ARRAY_SIZE(sercom_glck_freqs)];
-	double errors[ARRAY_SIZE(sercom_glck_freqs)];
-	for (uint8_t i = 0; i < ARRAY_SIZE(sercom_glck_freqs); i++) {
-		double freq = sercom_glck_freqs[i]; // remember possible SERCOM frequency
-		uint32_t min = freq / (2 * (255 + 1)); // calculate the minimum baud rate for this frequency
-		uint32_t max = freq / (2 * (0 + 1)); // calculate the maximum baud rate for this frequency
-		if (baudrate < min || baudrate > max) { // baud rate it out of supported range
-			errors[i] = NAN;
-		} else {
-			uint16_t baud = round(freq / (2 * baudrate) - 1);
-			bauds[i] = baud;
-			double actual = freq / (2 * (baud + 1));
-			errors[i] = fabs(1.0 - (actual / baudrate));
-		}
-	}
-
-	// find the smallest error
-	uint8_t best = ARRAY_SIZE(sercom_glck_freqs);
-	for (uint8_t i = 0; i < ARRAY_SIZE(sercom_glck_freqs); i++) {
-		if (isnan(errors[i])) {
-			continue;
-		}
-		if (best >= ARRAY_SIZE(sercom_glck_freqs)) {
-			best = i;
-		} else if (errors[i] < errors[best]) {
-			best = i;
-		}
-	}
-	if (best >= ARRAY_SIZE(sercom_glck_freqs)) { // found no clock supporting this baud rate
-		return false;
-	}
-
-	// set clock and baud rate
-	struct usart_async_descriptor* slot = SIM_peripheral_descriptors[slotnr]; // get slot
-	if (NULL == slot) {
-		return false;
-	}
-	printf("(%u) switching SERCOM clock to GCLK%u (freq = %lu kHz) and baud rate to %lu bps (baud = %u)\r\n", slotnr, (best + 1) * 2, (uint32_t)(round(sercom_glck_freqs[best] / 1000)), baudrate, bauds[best]);
-	while (!usart_async_is_tx_empty(slot)); // wait for transmission to complete (WARNING no timeout)
-	usart_async_disable(slot); // disable SERCOM peripheral
-	hri_gclk_clear_PCHCTRL_reg(GCLK, SIM_peripheral_GCLK_ID[slotnr], (1 << GCLK_PCHCTRL_CHEN_Pos)); // disable clock for this peripheral
-	while (hri_gclk_get_PCHCTRL_reg(GCLK, SIM_peripheral_GCLK_ID[slotnr], (1 << GCLK_PCHCTRL_CHEN_Pos))); // wait until clock is really disabled
-	// it does not seem we need to completely disable the peripheral using hri_mclk_clear_APBDMASK_SERCOMn_bit
-	hri_gclk_write_PCHCTRL_reg(GCLK, SIM_peripheral_GCLK_ID[slotnr], sercom_glck_sources[best] | (1 << GCLK_PCHCTRL_CHEN_Pos)); // set peripheral core clock and re-enable it
-	usart_async_set_baud_rate(slot, bauds[best]); // set the new baud rate
-	usart_async_enable(slot); // re-enable SERCOM peripheral
-
-	return true;
-}
-
-/** change ISO baud rate of card slot
- *  @param[in] slotnr slot number for which the baud rate should be set
- *  @param[in] clkdiv can clock divider
- *  @param[in] f clock rate conversion integer F
- *  @param[in] d baud rate adjustment factor D
- *  @return if the baud rate has been set, else a parameter is out of range
- */
-static bool slot_set_isorate(uint8_t slotnr, enum ncn8025_sim_clkdiv clkdiv, uint16_t f, uint8_t d)
-{
-	// input checks
-	ASSERT(slotnr < ARRAY_SIZE(SIM_peripheral_descriptors));
-	if (clkdiv != SIM_CLKDIV_1 && clkdiv != SIM_CLKDIV_2 && clkdiv != SIM_CLKDIV_4 && clkdiv != SIM_CLKDIV_8) {
-		return false;
-	}
-	if (!iso7816_3_valid_f(f)) {
-		return false;
-	}
-	if (!iso7816_3_valid_d(d)) {
-		return false;
-	}
-
-	// set clockdiv
-	struct ncn8025_settings settings;
-	ncn8025_get(slotnr, &settings);
-	if (settings.clkdiv != clkdiv) {
-		settings.clkdiv = clkdiv;
-		ncn8025_set(slotnr, &settings);
-	}
-
-	// calculate desired frequency
-	uint32_t freq = 20000000UL; // maximum frequency
-	switch (clkdiv) {
-	case SIM_CLKDIV_1:
-		freq /= 1;
-		break;
-	case SIM_CLKDIV_2:
-		freq /= 2;
-		break;
-	case SIM_CLKDIV_4:
-		freq /= 4;
-		break;
-	case SIM_CLKDIV_8:
-		freq /= 8;
-		break;
-	}
-
-	// set baud rate
-	uint32_t baudrate = (freq * d) / f; // calculate actual baud rate
-	return slot_set_baudrate(slotnr, baudrate); // set baud rate
-}
-
-/** write data to card
- *  @param[in] slotnr slot number on which to send data
- *  @param[in] data data to be transmitted
- *  @param[in] length length of data to be transmitted
- *  @return error code
- */
-static int slot_card_write(uint8_t slotnr, const uint8_t* data, uint16_t length)
-{
-	// input checks
-	ASSERT(slotnr < ARRAY_SIZE(SIM_peripheral_descriptors));
-	if (0 == length || NULL == data) {
-		return ERR_INVALID_ARG;
-	}
-
-	struct usart_async_descriptor* sim = SIM_peripheral_descriptors[slotnr];
-	((Sercom *)sim->device.hw)->USART.CTRLB.bit.RXEN = 0; // disable receive (to avoid the echo back)
-	SIM_tx_count[slotnr] = false; // reset TX complete
-	for (uint16_t i = 0; i < length; i++) { // transmit data
-		while(!usart_async_is_tx_empty(sim)); // wait for previous byte to be transmitted (WARNING blocking)
-		if (1 != io_write(&sim->io, &data[i], 1)) { // put but in transmit buffer
-			return ERR_IO;
-		}
-	}
-	while (!SIM_tx_count[slotnr]); // wait until transmission is complete (WARNING blocking)
-	((Sercom *)sim->device.hw)->USART.CTRLB.bit.RXEN = 1; // enable receive again
-
-	return ERR_NONE;
-}
-
-/** read data from card
- *  @param[in] slotnr slot number on which to send data
- *  @param[out] data buffer for read data to be stored
- *  @param[in] length length of data to be read
- *  @param[in] wt Waiting Time in ETU
- *  @return error code
- *  TODO fix WT/ETU duration
- */
-static int slot_card_read(uint8_t slotnr, uint8_t* data, uint16_t length, uint32_t wt)
-{
-	// input checks
-	ASSERT(slotnr < ARRAY_SIZE(SIM_peripheral_descriptors));
-	if (0 == length || NULL == data) {
-		return ERR_INVALID_ARG;
-	}
-
-	struct usart_async_descriptor* sim = SIM_peripheral_descriptors[slotnr];
-
-	((Sercom *)sim->device.hw)->USART.CTRLB.bit.RXEN = 1; // ensure RX is enabled
-	uint32_t timeout = wt; // reset waiting time
-	for (uint16_t i = 0; i < length; i++) { // read all data
-		while (timeout && !usart_async_is_rx_not_empty(sim)) { // verify if data is present
-			delay_us(149); // wait for 1 ETU (372 / 1 / 2.5 MHz = 148.8 us)
-			timeout--;
-		}
-		if (0 == timeout) { // timeout reached
-			return ERR_TIMEOUT;
-		}
-		timeout = wt; // reset waiting time
-		if (1 != io_read(&sim->io, &data[i], 1)) { // read one byte
-			return ERR_IO;
-		}
-	}
-
-	return ERR_NONE;
-}
-
-/** transfer TPDU
- *  @param[in] slotnr slot number on which to transfer the TPDU
- *  @param[in] header TPDU header to send
- *  @param[io] data TPDU data to transfer
- *  @param[in] data_length length of TPDU data to transfer
- *  @param[in] write if the data should be written (true) or read (false)
- * TODO fix WT
- * TODO the data length can be deduce from the header
- */
-static int slot_tpdu_xfer(uint8_t slotnr, const uint8_t* header, uint8_t* data, uint16_t data_length, bool write)
-{
-	// input checks
-	ASSERT(slotnr < ARRAY_SIZE(SIM_peripheral_descriptors));
-	if (NULL == header || (data_length > 0 && NULL == data)) {
-		return ERR_INVALID_ARG;
-	}
-
-	int rc;
-	struct usart_async_descriptor* sim = SIM_peripheral_descriptors[slotnr]; // get USART peripheral
-	usart_async_flush_rx_buffer(sim); // flush RX buffer to start from scratch
-
-	// send command header
-	printf("(%d) TPDU: ", slotnr);
-	for (uint8_t i = 0; i < 5; i++) {
-		printf("%02x ", header[i]);
-	}
-	rc = slot_card_write(slotnr, header, 5); // transmit header
-	if (ERR_NONE != rc) {
-		printf("error in command header transmit (errno = %d)\r\n", rc);
-		return rc;
-	}
-
-	// read procedure byte, and handle data
-	uint8_t pb = 0x60; // wait more procedure byte
-	uint16_t data_i = 0; // progress in the data transfer
-	while (0x60 == pb) { // wait for SW
-		rc = slot_card_read(slotnr, &pb, 1, ISO7816_3_DEFAULT_WT);
-		if (ERR_NONE != rc) {
-			printf("error while receiving PB/SW1 (errno = %d)\r\n", rc);
-			return rc;
-		}
-		printf("%02x ", pb);
-		if (0x60 == pb) { // NULL byte
-			// just wait more time
-		} else if ((0x60 == (pb & 0xf0)) || (0x90 == (pb & 0xf0))) { // SW1 byte
-			// left the rest of the code handle it
-		} else if (header[1] == pb) { // ACK byte
-			// transfer rest of the data
-			if (data_i >= data_length) {
-				printf("error no more data to transfer\r\n");
-				return ERR_INVALID_DATA;
-			}
-			if (write) { // transmit remaining command data
-				rc = slot_card_write(slotnr, &data[data_i], data_length - data_i); // transmit command data
-				if (ERR_NONE != rc) {
-					printf("error in command data transmit (errno = %d)\r\n", rc);
-					return rc;
-				}
-			} else { // receive remaining command data
-				rc = slot_card_read(slotnr, &data[data_i], data_length - data_i, ISO7816_3_DEFAULT_WT);
-				if (ERR_NONE != rc) {
-					printf("error in command data receive (errno = %d)\r\n", rc);
-					return rc;
-				}
-			}
-			for (uint16_t i = data_i; i < data_length; i++) {
-				printf("%02x ", data[i]);
-			}
-			data_i = data_length; // remember we transferred the data
-			pb = 0x60; // wait for SW1
-		} else if (header[1] == (pb ^ 0xff)) { // ACK byte
-			// transfer only one byte
-			if (data_i >= data_length) {
-				printf("error no more data to transfer\r\n");
-				return ERR_INVALID_DATA;
-			}
-			if (write) { // transmit command data byte
-				rc = slot_card_write(slotnr, &data[data_i], 1); // transmit command data
-				if (ERR_NONE != rc) {
-					printf("error in command data transmit (errno = %d)\r\n", rc);
-					return rc;
-				}
-			} else { // receive command data byte
-				rc = slot_card_read(slotnr, &data[data_i], 1, ISO7816_3_DEFAULT_WT);
-				if (ERR_NONE != rc) {
-					printf("error in command data receive (errno = %d)\r\n", rc);
-					return rc;
-				}
-			}
-			printf("%02x ", data[data_i]);
-			data_i += 1; // remember we transferred one data byte
-			pb = 0x60; // wait for SW1
-		} else { // invalid byte
-			return ERR_INVALID_DATA;
-		}
-	}
-
-	// read SW2
-	uint8_t sw2;
-	rc = slot_card_read(slotnr, &sw2, 1, ISO7816_3_DEFAULT_WT);
-	if (ERR_NONE != rc) {
-		printf("error in receiving SW2 (errno = %d)\r\n", rc);
-		return rc;
-	}
-	printf("%02x", sw2);
-
-	printf("\r\n");
-	return ERR_NONE;
-}
-
-DEFUN(sim_status, cmd_sim_status, "sim-status", "Get state of specified NCN8025")
-{
-	struct ncn8025_settings settings;
-	int slotnr = validate_slotnr(argc, argv, 1);
-	if (slotnr < 0)
-		return;
-	ncn8025_get(slotnr, &settings);
-	printf("SIM%d: ", slotnr);
-	ncn8025_dump(&settings);
-	printf("\r\n");
-}
-
-DEFUN(sim_power, cmd_sim_power, "sim-power", "Enable/disable SIM card power")
-{
-	struct ncn8025_settings settings;
-	int slotnr = validate_slotnr(argc, argv, 1);
-	int enable;
-
-	if (slotnr < 0)
-		return;
-
-	if (argc < 3) {
-		printf("You have to specify 0=disable or 1=enable\r\n");
-		return;
-	}
-	enable = atoi(argv[2]);
-	ncn8025_get(slotnr, &settings);
-	if (enable)
-		settings.cmdvcc = true;
-	else
-		settings.cmdvcc = false;
-	ncn8025_set(slotnr, &settings);
-}
-
-DEFUN(sim_reset, cmd_sim_reset, "sim-reset", "Enable/disable SIM reset")
-{
-	struct ncn8025_settings settings;
-	int slotnr = validate_slotnr(argc, argv, 1);
-	int enable;
-
-	if (slotnr < 0)
-		return;
-
-	if (argc < 3) {
-		printf("You have to specify 0=disable or 1=enable\r\n");
-		return;
-	}
-	enable = atoi(argv[2]);
-	ncn8025_get(slotnr, &settings);
-	if (enable)
-		settings.rstin = true;
-	else
-		settings.rstin = false;
-	ncn8025_set(slotnr, &settings);
-}
-
-DEFUN(sim_clkdiv, cmd_sim_clkdiv, "sim-clkdiv", "Set SIM clock divider (1,2,4,8)")
-{
-	struct ncn8025_settings settings;
-	int slotnr = validate_slotnr(argc, argv, 1);
-	int clkdiv;
-
-	if (slotnr < 0)
-		return;
-
-	if (argc < 3) {
-		printf("You have to specify a valid divider (1,2,4,8)\r\n");
-		return;
-	}
-	clkdiv = atoi(argv[2]);
-	if (clkdiv != 1 && clkdiv != 2 && clkdiv != 4 && clkdiv != 8) {
-		printf("You have to specify a valid divider (1,2,4,8)\r\n");
-		return;
-	}
-	ncn8025_get(slotnr, &settings);
-	switch (clkdiv) {
-	case 1:
-		settings.clkdiv = SIM_CLKDIV_1;
-		break;
-	case 2:
-		settings.clkdiv = SIM_CLKDIV_2;
-		break;
-	case 4:
-		settings.clkdiv = SIM_CLKDIV_4;
-		break;
-	case 8:
-		settings.clkdiv = SIM_CLKDIV_8;
-		break;
-	}
-	ncn8025_set(slotnr, &settings);
-}
-
-DEFUN(sim_voltage, cmd_sim_voltage, "sim-voltage", "Set SIM voltage (5/3/1.8)")
-{
-	struct ncn8025_settings settings;
-	int slotnr = validate_slotnr(argc, argv, 1);
-
-	if (slotnr < 0)
-		return;
-
-	if (argc < 3) {
-		printf("You have to specify a valid voltage (5/3/1.8)\r\n");
-		return;
-	}
-	ncn8025_get(slotnr, &settings);
-	if (!strcmp(argv[2], "5"))
-		settings.vsel = SIM_VOLT_5V0;
-	else if (!strcmp(argv[2], "3"))
-		settings.vsel = SIM_VOLT_3V0;
-	else if (!strcmp(argv[2], "1.8"))
-		settings.vsel = SIM_VOLT_1V8;
-	else {
-		printf("You have to specify a valid voltage (5/3/1.8)\r\n");
-		return;
-	}
-	ncn8025_set(slotnr, &settings);
-}
-
-DEFUN(sim_led, cmd_sim_led, "sim-led", "Set SIM LED (1=on, 0=off)")
-{
-	struct ncn8025_settings settings;
-	int slotnr = validate_slotnr(argc, argv, 1);
-
-	if (slotnr < 0)
-		return;
-
-	if (argc < 3) {
-		printf("You have to specify 0=disable or 1=enable\r\n");
-		return;
-	}
-	ncn8025_get(slotnr, &settings);
-	if (atoi(argv[2]))
-		settings.led = true;
-	else
-		settings.led = false;
-	ncn8025_set(slotnr, &settings);
-}
-
-DEFUN(sim_atr, cmd_sim_atr, "sim-atr", "Read ATR from SIM card")
-{
-	struct ncn8025_settings settings;
-	int slotnr = validate_slotnr(argc, argv, 1);
-
-	if (slotnr < 0 || slotnr >= ARRAY_SIZE(SIM_peripheral_descriptors) || NULL == SIM_peripheral_descriptors[slotnr]) {
-		return;
-	}
-
-	// check if card is present (and read current settings)
-	ncn8025_get(slotnr, &settings);
-	if (!settings.simpres) {
-		printf("(%d) error: no card present\r\n", slotnr);
-		return;
-	}
-
-	// switch card off (assert reset and disable power)
-	// note: ISO/IEC 7816-3:2006 section 6.4 provides the deactivation sequence, but not the minimum corresponding times
-	settings.rstin = true;
-	settings.cmdvcc = false;
-	settings.led = true;
-	ncn8025_set(slotnr, &settings);
-
-	// TODO wait some time for card to be completely deactivated
-	usart_async_flush_rx_buffer(SIM_peripheral_descriptors[slotnr]); // flush RX buffer to start from scratch
-
-	
-	// set clock to lowest frequency (20 MHz / 8 = 2.5 MHz)
-	// note: according to ISO/IEC 7816-3:2006 section 5.2.3 the minimum value is 1 MHz, and maximum is 5 MHz during activation
-	settings.clkdiv = SIM_CLKDIV_8;
-	// set USART baud rate to match the interface (f = 2.5 MHz) and card default settings (Fd = 372, Dd = 1)
-	slot_set_isorate(slotnr, settings.clkdiv, ISO7816_3_DEFAULT_FD, ISO7816_3_DEFAULT_DD);
-	// set card voltage to 3.0 V (the most supported)
-	// note: according to ISO/IEC 7816-3:2006 no voltage should damage the card, and you should cycle from low to high
-	settings.vsel = SIM_VOLT_3V0;
-	// provide power (the NCN8025 should perform the activation according to spec)
-	// note: activation sequence is documented in ISO/IEC 7816-3:2006 section 6.2
-	settings.cmdvcc = true;
-	ncn8025_set(slotnr, &settings);
-
-	// wait for Tb=400 cycles before re-asserting reset
-	delay_us(400 * 10000 / 2500); // 400 cycles * 1000 for us, 2.5 MHz / 1000 for us
-
-	// de-assert reset to switch card back on
-	settings.rstin = false;
-	ncn8025_set(slotnr, &settings);
-
-	// wait for Tc=40000 cycles for transmission to start
-	uint32_t cycles = 40000;
-	while (cycles && !usart_async_is_rx_not_empty(SIM_peripheral_descriptors[slotnr])) {
-		delay_us(10);
-		cycles -= 25; // 10 us = 25 cycles at 2.5 MHz
-	}
-	if (!usart_async_is_rx_not_empty(SIM_peripheral_descriptors[slotnr])) {
-		delay_us(12 * 372 / 1 / 2); // wait more than one byte (approximate freq down to 2 MHz)
-	}
-	// verify if one byte has been received
-	if (!usart_async_is_rx_not_empty(SIM_peripheral_descriptors[slotnr])) {
-		printf("(%d) error: card not responsive\r\n", slotnr);
-		return;
-	}
-
-	// read ATR (just do it until there is no traffic anymore)
-	// TODO the ATR should be parsed to read the right number of bytes, instead we just wait until to end of WT
-	printf("(%d) ATR: ", slotnr);
-	uint8_t atr_byte;
-	while (usart_async_is_rx_not_empty(SIM_peripheral_descriptors[slotnr])) {
-		if (1 == io_read(&SIM_peripheral_descriptors[slotnr]->io, &atr_byte, 1)) {
-			printf("%02x ", atr_byte);
-		}
-		uint16_t wt = ISO7816_3_DEFAULT_WT; // waiting time in ETU
-		while (wt && !usart_async_is_rx_not_empty(SIM_peripheral_descriptors[slotnr])) {
-			delay_us(149); // wait for 1 ETU (372 / 1 / 2.5 MHz = 148.8 us)
-			wt--;
-		}
-	}
-	printf("\r\n");
-
-	/* disable LED */
-	settings.led = false;
-	ncn8025_set(slotnr, &settings);
-}
-
-DEFUN(sim_iccid, cmd_sim_iccid, "sim-iccid", "Read ICCID from SIM card")
-{
-	struct ncn8025_settings settings;
-	int slotnr = validate_slotnr(argc, argv, 1);
-
-	if (slotnr < 0 || slotnr >= ARRAY_SIZE(SIM_peripheral_descriptors) || NULL == SIM_peripheral_descriptors[slotnr]) {
-		return;
-	}
-
-	// read current settings and check if card is present and powered
-	ncn8025_get(slotnr, &settings);
-	if (!settings.simpres) {
-		printf("(%d) error: no card present\r\n", slotnr);
-		return;
-	}
-	if (!settings.cmdvcc) {
-		printf("(%d) error: card not powered\r\n", slotnr);
-		return;
-	}
-	if (settings.rstin) {
-		printf("(%d) error: card under reset\r\n", slotnr);
-		return;
-	}
-
-	// enable LED
-	if (!settings.led) {
-		settings.led = true;
-		ncn8025_set(slotnr, &settings);
-	}
-
-	// select MF
-	printf("(%d) SELECT MF\r\n", slotnr);
-	const uint8_t select_header[] = {0xa0, 0xa4, 0x00, 0x00, 0x02}; // see TS 102.221 sec. 11.1.1
-	const uint8_t select_data_mf[] = {0x3f, 0x00}; // see TS 102.221 sec. 13.1
-	int rc = slot_tpdu_xfer(slotnr, select_header, (uint8_t*)select_data_mf, ARRAY_SIZE(select_data_mf), true); // transfer TPDU
-	if (ERR_NONE != rc) {
-		printf("error while SELECT MF (errno = %d)\r\n", rc);
-	}
-	// ignore response data
-
-	// select EF_ICCID
-	printf("(%d) SELECT EF_ICCID\r\n", slotnr);
-	const uint8_t select_data_ef_iccid[] = {0x2f, 0xe2}; // see TS 102.221 sec. 13.2
-	rc = slot_tpdu_xfer(slotnr, select_header, (uint8_t*)select_data_ef_iccid, ARRAY_SIZE(select_data_ef_iccid), true); // transfer TPDU
-	if (ERR_NONE != rc) {
-		printf("error while SELECT EF_ICCID (errno = %d)\r\n", rc);
-	}
-	// ignore response data
-
-	// read EF_ICCID
-	printf("(%d) READ EF_ICCID\r\n", slotnr);
-	uint8_t iccid[10];
-	uint8_t read_binary[] = {0xa0, 0xb0, 0x00, 0x00, ARRAY_SIZE(iccid)}; // see TS 102.221 sec. 11.1.3
-	rc = slot_tpdu_xfer(slotnr, read_binary, iccid, ARRAY_SIZE(iccid), false); // transfer TPDU
-	if (ERR_NONE != rc) {
-		printf("error while READ ICCID (errno = %d)\r\n", rc);
-	}
-	// ignore response data
-
-	printf("(%d) ICCID: ", slotnr);
-	for (uint8_t i = 0; i < ARRAY_SIZE(iccid); i++) {
-		uint8_t nibble = iccid[i] & 0xf;
-		if (0xf == nibble) {
-			break;
-		}
-		printf("%x", nibble);
-		nibble = iccid[i] >> 4;
-		if (0xf == nibble) {
-			break;
-		}
-		printf("%x", nibble);
-	}
-	printf("\r\n");
-
-	// disable LED
-	settings.led = false;
-	ncn8025_set(slotnr, &settings);
-}
-
-DEFUN(get_time, cmd_get_time, "get-time", "Read Time from RTC")
-{
-	struct calendar_date_time dt;
-	calendar_get_date_time(&CALENDAR_0, &dt);
-	printf("%04u-%02u-%02u %02u:%02u:%02u\r\n", dt.date.year, dt.date.month, dt.date.day,
-		dt.time.hour, dt.time.min, dt.time.sec);
-}
-
-#include <osmocom/core/timer.h>
-static struct osmo_timer_list t;
-static void tmr_cb(void *data)
-{
-	printf("timer fired!\r\n");
-}
-DEFUN(test_timer, cmd_test_timer, "test-timer", "Test osmo_timer")
-{
-	printf("Setting up timer for 3s...\n\r");
-	osmo_timer_setup(&t, &tmr_cb, NULL);
-	osmo_timer_schedule(&t, 3, 0);
-}
-
 
 extern void testmode_init(void);
 extern void libosmo_emb_init(void);
@@ -993,25 +330,9 @@
 
 #include "talloc.h"
 #include "logging.h"
-#include <osmocom/core/msgb.h>
+
 void *g_tall_ctx;
 
-DEFUN(_talloc_report, cmd_talloc_report, "talloc-report", "Generate a talloc report")
-{
-	talloc_report_full(g_tall_ctx, stdout);
-}
-
-DEFUN(talloc_test, cmd_talloc_test, "talloc-test", "Test the talloc allocator")
-{
-	for (int i = 0; i < 10; i++)
-		talloc_named_const(g_tall_ctx, 10, "sibling");
-}
-
-DEFUN(v_talloc_free, cmd_talloc_free, "talloc-free", "Release all memory")
-{
-	talloc_free(g_tall_ctx);
-	g_tall_ctx = NULL;
-}
 
 /* Section 9.6 of SAMD5x/E5x Family Data Sheet */
 static int get_chip_unique_serial(uint8_t *out, size_t len)
@@ -1067,6 +388,55 @@
 		strcat(out, "BACKUP ");
 }
 
+//#######################
+
+
+
+static uint32_t clock_freqs[] = {
+	2500000
+};
+
+static uint32_t data_rates[] = {
+	6720
+};
+extern struct usb_desc_collection usb_fs_descs;
+
+
+
+static int feed_ccid(void)
+{
+	struct usb_ep_q *ep_q = &g_ccid_s.out_ep;
+	struct msgb *msg;
+	int rc;
+
+	msg = msgb_dequeue_irqsafe(&g_ccid_s.out_ep.list);
+	if (!msg)
+		return -1;
+
+	ccid_handle_out(&g_ci, msg);
+	return 1;
+}
+
+static int ccid_ops_send_in(struct ccid_instance *ci, struct msgb *msg)
+{
+	/* add just-received msg to tail of endpoint queue */
+	OSMO_ASSERT(msg);
+
+	/* append to list of pending-to-be-handed messages */
+	llist_add_tail_at(&msg->list, &g_ccid_s.in_ep.list);
+	submit_next_in();
+	return 0;
+}
+
+static const struct ccid_ops c_ops = {
+	.send_in = ccid_ops_send_in,
+	.send_int = 0,
+};
+
+//#######################
+
+#define NUM_OUT_BUF 7
+
 int main(void)
 {
 	char sernr_buf[16*2+1];
@@ -1080,20 +450,6 @@
 
 	board_init();
 	command_init("sysmoOCTSIM> ");
-	command_register(&cmd_sim_status);
-	command_register(&cmd_sim_power);
-	command_register(&cmd_sim_reset);
-	command_register(&cmd_sim_clkdiv);
-	command_register(&cmd_sim_voltage);
-	command_register(&cmd_sim_led);
-	command_register(&cmd_sim_atr);
-	command_register(&cmd_sim_iccid);
-	testmode_init();
-	command_register(&cmd_talloc_test);
-	command_register(&cmd_talloc_report);
-	command_register(&cmd_talloc_free);
-	command_register(&cmd_get_time);
-	command_register(&cmd_test_timer);
 
 	printf("\r\n\r\n"
 		"=============================================================================\n\r"
@@ -1111,11 +467,39 @@
 
 	LOGP(DUSB, LOGL_ERROR, "foobar usb\n");
 
-	command_print_prompt();
+	ccid_instance_init(&g_ci, &c_ops, &iso_fsm_slot_ops, &usb_fs_descs.ccid.class,
+			   data_rates, clock_freqs, "", 0);
+
+	for(int i =0; i < NUM_OUT_BUF; i++){
+		struct msgb *msg = msgb_alloc(300, "ccid");
+		OSMO_ASSERT(msg);
+		/* return the message back to the queue of free message buffers */
+		llist_add_tail_at(&msg->list, &g_ccid_s.free_q);
+	}
+	submit_next_out();
+
+//	command_print_prompt();
 	while (true) { // main loop
 		command_try_recv();
 		poll_card_detect();
 		submit_next_irq();
+		feed_ccid();
 		osmo_timers_update();
+		int qs = llist_count_at(&g_ccid_s.free_q);
+		if(qs > NUM_OUT_BUF)
+			for (int i= 0; i < qs-NUM_OUT_BUF; i++){
+				struct msgb *msg = msgb_dequeue_irqsafe(&g_ccid_s.free_q);
+				if (msg)
+				msgb_free(msg);
+			}
+		if(qs < NUM_OUT_BUF)
+			for (int i= 0; i < qs-NUM_OUT_BUF; i++){
+				struct msgb *msg = msgb_alloc(300,"ccid");
+				OSMO_ASSERT(msg);
+				/* return the message back to the queue of free message buffers */
+				llist_add_tail_at(&msg->list, &g_ccid_s.free_q);
+			}
+
+
 	}
 }