1c56c776_RCX_Manual__RCX_device_controlled
[Device registers] device registers of I/O port 6. Two lines of port 6 are used [Interrupts] no interrupts [RCX device controlled] 
LCD
b u t t o n s
i n p u t p o r t s
b a t t e r y v o l t a g e l e v e l
t i m e r s
i n f r a r e d t r a n s m i t t e r / r e c e i v e r
L C D
s p e a k e r
o u t p u t p o r t s
RCX Manual
RCX device controlled