diff --git a/tests/periph_timer/Makefile b/tests/periph_timer/Makefile
index 1debd39325..07e78eaaca 100644
--- a/tests/periph_timer/Makefile
+++ b/tests/periph_timer/Makefile
@@ -6,4 +6,11 @@ FEATURES_REQUIRED = periph_timer
 
 TEST_ON_CI_WHITELIST += all
 
+ifneq (,$(filter arduino-duemilanove arduino-mega2560 arduino-uno waspmote-pro,$(BOARD)))
+  TIMER_SPEED ?= 250000
+endif
+
+TIMER_SPEED ?= 1000000
+
+CFLAGS += -DTIMER_SPEED=$(TIMER_SPEED)
 include $(RIOTBASE)/Makefile.include
diff --git a/tests/periph_timer/README.md b/tests/periph_timer/README.md
new file mode 100644
index 0000000000..72e6434297
--- /dev/null
+++ b/tests/periph_timer/README.md
@@ -0,0 +1,17 @@
+# Periph Timer Test
+
+## About
+
+This application will test all configured peripheral timers of the target
+platform. For each timer, it will set each channel with an incrementing
+timeout: CH0 is set to 5ms, CH1 to 10ms, CH2 to 15ms and so on.
+
+## Expected Result
+
+The output should show that every channel fired after an evenly distributed
+amount of time, i.e. the diff values should be equal (with some jitter...).
+
+## Note
+
+This test does however **NOT** show whether the timeouts and diffs were correct
+in relation to the expected real-time; use e.g. tests/xtimer_msg for this.
diff --git a/tests/periph_timer/main.c b/tests/periph_timer/main.c
index ad75ea662a..1cd0a9e39b 100644
--- a/tests/periph_timer/main.c
+++ b/tests/periph_timer/main.c
@@ -32,7 +32,6 @@
 #endif
 
 #define MAX_CHANNELS        (10U)
-#define TIM_SPEED           (1000000ul) /* try to run with 1MHz */
 #define CHAN_OFFSET         (5000U)     /* fire every 5ms */
 #define COOKIE              (100U)      /* for checking if arg is passed */
 
@@ -61,7 +60,7 @@ static int test_timer(unsigned num)
     }
 
     /* initialize and halt timer */
-    if (timer_init(TIMER_DEV(num), TIM_SPEED, cb, (void *)(COOKIE * num)) < 0) {
+    if (timer_init(TIMER_DEV(num), TIMER_SPEED, cb, (void *)(COOKIE * num)) < 0) {
         printf("TIMER_%u: ERROR on initialization - skipping\n\n", num);
         return 0;
     }
@@ -115,16 +114,6 @@ int main(void)
     int res = 0;
 
     puts("\nTest for peripheral TIMERs\n");
-    puts("This test will test all configured peripheral timers of the\n"
-         "targeted platform. For each timer, it will set each channel with\n"
-         "an incrementing timeout. CH0 set to 5ms, CH1 to 10ms, CH2 to 15ms\n"
-         "and so on.\n"
-         "In the output you should see that every channel fired, after an\n"
-         "evenly distributed amount of time -> the shown diff values should\n"
-         "be pretty much equal (to some jitter...)\n"
-         "This test does however NOT show, if the timeouts were correct in\n"
-         "relation to the expected real-time ~ use e.g. tests/xtimer_msg for\n"
-         "this.\n\n");
 
     printf("Available timers: %i\n", TIMER_NUMOF);