Propeller Programming: Using Assembler, Spin, and C

© Sridhar Anandakrishnan 2018

Sridhar AnandakrishnanPropeller Programminghttps://doi.org/10.1007/978-1-4842-3354-2_7

7. Interacting with the World

Sridhar Anandakrishnan¹ 

(1)

Department of Geosciences, University Park, Pennsylvania, USA

 

One of the main uses of a Propeller is to “talk” to hardware such as motors, relays, switches, LEDs, and so on. In the Propeller there are 32 general-purpose input/output pins, P0–P31. Figure 7-1 shows an overview of the relationship between the cogs and pins. Pins P30 and P31 are usually reserved for the programming and serial ports. Pins P28 and P29 are usually tied to an electrically erasable programmable read-only memory (EEPROM) that stores the program even when there is no power applied. So, pins P0–P27 are ...