io interface; relying on patched lwip

bsp_z7/hardware/uart.c

@@ -77,6 +77,7 @@ void uart0_enable_receiver() {
 }
 
 int uart0_read(char *ptr, int len) {
+  // TODO for blocking, if first call was successfull, further calls need to be delay=0
   int received = 0;
   while (len > 0) {
     BaseType_t result = xQueueReceive(uart0_receive_queue, ptr, 0);