COE 758 Lecture Notes - Lecture 6: Device Driver, Spooling, Eeprom

• School: Ryerson University
• Department: Computer Engineering
• Course: COE 758
• Professor: Nagi Mekhiel

Document Summary

Software goals of input/output a. b. c. d. e. Generates a request that passes it to the os. Hide the details of each device, has initialization, control. When the device finishes, it generates interrupt to processor. Oragnization - connects input/output devices through a bus to processor memory bus. Controller has registers that maps to processor memory: Status: memory mapped registers can initialize data transfer through initializing: size of data to be transferred and starting address. Transfer 1kb from location 1000, then the controller knows that it wants to transfer that 1kb in or out using dma (direct memory access). When it finishes transferring data, the controller interrupts the processor. I/o slowest portion of system is amdhahl"s law. Spin platters, so that head is on top of sector. 8 sectors in a track and then it takes 8 revolution revs to access a full track.