diff --git a/cpu/lpc2387/include/cpu.h b/cpu/lpc2387/include/cpu.h
index f197da35bb..fc8f179c4f 100644
--- a/cpu/lpc2387/include/cpu.h
+++ b/cpu/lpc2387/include/cpu.h
@@ -50,7 +50,7 @@ static inline void cpu_print_last_instruction(void)
 {
     register uint32_t *lr_ptr;
     __asm__ __volatile__("mov %0, lr" : "=r"(lr_ptr));
-    printf("%p\n", lr_ptr);
+    printf("%p\n", (void*) lr_ptr);
 }
 
 #ifdef __cplusplus
diff --git a/cpu/lpc2387/periph/gpio.c b/cpu/lpc2387/periph/gpio.c
index 6576fae7ce..028f4769f6 100644
--- a/cpu/lpc2387/periph/gpio.c
+++ b/cpu/lpc2387/periph/gpio.c
@@ -69,6 +69,7 @@ static int _isr_map_entry(gpio_t pin) {
 
 int gpio_init(gpio_t pin, gpio_dir_t dir, gpio_pp_t pullup)
 {
+    (void) dir;
     unsigned _pin = pin & 31;
     unsigned port = pin >> 5;
 
@@ -88,7 +89,9 @@ int gpio_init(gpio_t pin, gpio_dir_t dir, gpio_pp_t pullup)
     return 0;
 }
 
-int gpio_init_mux(unsigned pin, unsigned mux) {
+int gpio_init_mux(unsigned pin, unsigned mux)
+{
+    (void) mux;
     unsigned _pin = pin & 31;
     PINSEL[pin>>4] &= ~(0x1 << (_pin*2));
     return 0;
diff --git a/cpu/lpc2387/periph/rtc.c b/cpu/lpc2387/periph/rtc.c
index 7eca711b31..d239676818 100644
--- a/cpu/lpc2387/periph/rtc.c
+++ b/cpu/lpc2387/periph/rtc.c
@@ -97,6 +97,7 @@ int rtc_get_time(struct tm *localt)
 
 int rtc_set_alarm(struct tm *localt, rtc_alarm_cb_t cb, void *arg)
 {
+    (void) arg;
     if (localt != NULL) {
         RTC_ALSEC = localt->tm_sec;
         RTC_ALMIN = localt->tm_min;
diff --git a/cpu/lpc2387/periph/spi.c b/cpu/lpc2387/periph/spi.c
index d7dae92eff..4967a2a65a 100644
--- a/cpu/lpc2387/periph/spi.c
+++ b/cpu/lpc2387/periph/spi.c
@@ -50,6 +50,7 @@ static mutex_t locks[] =  {
 
 int spi_init_master(spi_t dev, spi_conf_t conf, spi_speed_t speed)
 {
+    (void ) conf;
     if (dev) {
         return -1;
     }
@@ -170,6 +171,7 @@ int spi_release(spi_t dev)
 
 int spi_transfer_byte(spi_t dev, char out, char *in)
 {
+    (void) dev;
     while (!SPI_TX_EMPTY);
     SSP0DR = out;
     while (SPI_BUSY);
@@ -186,10 +188,13 @@ int spi_transfer_byte(spi_t dev, char out, char *in)
 
 void spi_poweron(spi_t dev)
 {
+    (void) dev;
 }
 
 void spi_poweroff(spi_t dev)
 {
+    (void) dev;
+    (void) dev;
 }
 
 int spi_conf_pins(spi_t dev)
diff --git a/cpu/lpc2387/periph/timer.c b/cpu/lpc2387/periph/timer.c
index cdf469cd89..c8cf22c33b 100644
--- a/cpu/lpc2387/periph/timer.c
+++ b/cpu/lpc2387/periph/timer.c
@@ -140,7 +140,7 @@ int timer_set(tim_t tim, int channel, unsigned int timeout)
 
 int timer_set_absolute(tim_t tim, int channel, unsigned int value)
 {
-    if (tim >= TIMER_NUMOF || channel >= TIMER_CHAN_NUMOF) {
+    if (((unsigned) tim >= TIMER_NUMOF) || ((unsigned) channel >= TIMER_CHAN_NUMOF)) {
         return -1;
     }
 
@@ -152,7 +152,7 @@ int timer_set_absolute(tim_t tim, int channel, unsigned int value)
 
 int timer_clear(tim_t tim, int channel)
 {
-    if (tim >= TIMER_NUMOF || channel >= TIMER_CHAN_NUMOF) {
+    if (((unsigned) tim >= TIMER_NUMOF) || ((unsigned) channel >= TIMER_CHAN_NUMOF)) {
         return -1;
     }
     get_dev(tim)->MCR &= ~(1 << (channel * 3));
@@ -176,17 +176,19 @@ void timer_stop(tim_t tim)
 
 void timer_irq_enable(tim_t tim)
 {
+    (void) tim;
     /* TODO */
 }
 
 void timer_irq_disable(tim_t tim)
 {
+    (void) tim;
     /* TODO */
 }
 
 static inline void isr_handler(lpc23xx_timer_t *dev, int tim_num)
 {
-    for (int i = 0; i < TIMER_CHAN_NUMOF; i++) {
+    for (unsigned i = 0; i < TIMER_CHAN_NUMOF; i++) {
         if (dev->IR & (1 << i)) {
             dev->IR |= (1 << i);
             dev->MCR &= ~(1 << (i * 3));
diff --git a/cpu/lpc2387/periph/uart.c b/cpu/lpc2387/periph/uart.c
index 7c95598dfe..a0637816a5 100644
--- a/cpu/lpc2387/periph/uart.c
+++ b/cpu/lpc2387/periph/uart.c
@@ -37,6 +37,7 @@ void UART0_IRQHandler(void) __attribute__((interrupt("IRQ")));
 
 int uart_init(uart_t dev, uint32_t baudrate, uart_rx_cb_t rx_cb, void *arg)
 {
+    (void) baudrate;
     /* for now, we only support one UART device and only the RX interrupt */
     if (dev != 0) {
         return -1;
@@ -71,6 +72,7 @@ int uart_init(uart_t dev, uint32_t baudrate, uart_rx_cb_t rx_cb, void *arg)
 
 void uart_write(uart_t uart, const uint8_t *data, size_t len)
 {
+    (void) uart;
     for (size_t i = 0; i < len; i++) {
         while (!(U0LSR & BIT5));
         U0THR = data[i];