Arduino LED blink with uLisp

blink.lisp

;; Arduino LED blink
;;
;; Based on the example at http://www.ulisp.com/show?1LG8
;;
;; 2017, Frederico Munoz <fsmunoz@sdf.org>


(defun b (x s d)
  "Slowly increases and decreases the blinking interval in a loop"
  (pinmode 13 t)
  (digitalwrite 13 x)
  (delay s)
  (cond
   ((< s 100) (b (not x) (+ s 50) 50))
   ((> s 1000) (b (not x) (- s 50) -50))
   (t (b (not x) (+ s d) d))))

(b t 500 50)