Cleaned out libmaple.h; this had wide-ranging implications.

Many of the #defines in libmaple.h were board-specific, not
MCU-specific.  Most of these were only used by code under
libmaple/usb/.  These were moved into usb_config.h, and are clearly
marked as being terrible hacks.  I'm going to treat the USB stack as a
black box that we'll deal with later.

Further, instead of having a variety of #defines like "How many USARTS
do I have?", we decide that based on the density of the chip.  This is
determined by testing for STM32_MEDIUM_DENSITY or STM32_HIGH_DENSITY
defines.  libmaple currently doesn't support low-density chips, so
that suffices.  The Makefile will set these automatically based on the
MCU.

Other offending #defines are ERROR_LED_PORT and ERROR_LED_PIN; these
were made optional, but they're set in the Makefile as a hack to keep
things working.

2 files changed, 21 insertions, 20 deletions

diff --git a/examples/test-bkp.cpp b/examples/test-bkp.cpp
index 27f87bd..d0aa564 100644
--- a/examples/test-bkp.cpp
+++ b/examples/test-bkp.cpp
@@ -7,59 +7,61 @@
 void print_bkp_contents();
 void write_to_bkp(uint16 val);
 
+#define comm Serial2
+
 void setup() {
     pinMode(BOARD_BUTTON_PIN, INPUT);
 
-    Serial2.begin(9600);
-    Serial2.println("*** Beginning BKP test");
+    comm.begin(9600);
+    comm.println("*** Beginning BKP test");
 
-    Serial2.println("Init...");
+    comm.println("Init...");
     bkp_init();
-    Serial2.println("Done.");
+    comm.println("Done.");
 
     print_bkp_contents();
     write_to_bkp(10);
     print_bkp_contents();
 
-    Serial2.println("Enabling backup writes.");
+    comm.println("Enabling backup writes.");
     bkp_enable_writes();
     write_to_bkp(20);
     print_bkp_contents();
 
-    Serial2.println("Disabling backup writes.");
+    comm.println("Disabling backup writes.");
     bkp_disable_writes();
     write_to_bkp(30);
     print_bkp_contents();
 
-    Serial2.println("Done testing backup registers; press button to enable "
+    comm.println("Done testing backup registers; press button to enable "
                     "independent watchdog (in order to cause a reset).");
     waitForButtonPress(0);
     iwdg_init(IWDG_PRE_4, 1);
-    Serial2.println();
+    comm.println();
 }
 
 void loop() {
 }
 
 void print_bkp_contents() {
-    Serial2.println("Backup data register contents:");
+    comm.println("Backup data register contents:");
     char buf[100];
-    for (int i = 1; i <= NR_BKP_REGS; i++) {
+    for (int i = 1; i <= BKP_NR_DATA_REGS; i++) {
         snprintf(buf, sizeof buf, "DR%d: %d ", i, bkp_read(i));
-        Serial2.print(buf);
-        if (i % 5 == 0) Serial2.println();
+        comm.print(buf);
+        if (i % 5 == 0) comm.println();
     }
-    Serial2.println();
+    comm.println();
 }
 
 void write_to_bkp(uint16 val) {
-    Serial2.print("Attempting to write ");
-    Serial2.print(val);
-    Serial2.println(" to backup registers...");
-    for (int i = 1; i <= NR_BKP_REGS; i++) {
+    comm.print("Attempting to write ");
+    comm.print(val);
+    comm.println(" to backup registers...");
+    for (int i = 1; i <= BKP_NR_DATA_REGS; i++) {
         bkp_write(i, val);
     }
-    Serial2.println("Done.");
+    comm.println("Done.");
 }
 
 __attribute__((constructor)) void premain() {
diff --git a/examples/test-session.cpp b/examples/test-session.cpp
index 86bab6d..72d64d6 100644
--- a/examples/test-session.cpp
+++ b/examples/test-session.cpp
@@ -614,9 +614,8 @@ void init_all_timers(uint16 prescale) {
     timer_init(TIMER1, prescale);
     timer_init(TIMER2, prescale);
     timer_init(TIMER3, prescale);
-#if NR_TIMERS >= 4
     timer_init(TIMER4, prescale);
-#elif NR_TIMERS >= 8 // TODO test this on maple native
+#ifdef STM32_HIGH_DENSITY
     timer_init(TIMER5, prescale);
     timer_init(TIMER6, prescale);
     timer_init(TIMER7, prescale);