91.305 MIDTERM NOTES

YOU CAN BRING ALL DATA SHEETS!  IN FACT, DEFINITELY BRING THEM UNLESS
YOU HAVE A PHOTOGRAPHIC MEMORY.

1 PAGE OF PERSONALLY PREPARED NOTES (BOTH SIDES) MAY ALSO BE BROUGHT.
THESE ARE TO BE TURNED IN WITH EXAM (YOU WILL GET BACK).

V= IR  (calculating voltage, current, and resistance given 2 of 3)

NPN transistor circuits (models of current flow, BE current x beta
  (gain) yields CE current)

electrical properties of digital logic (input current, output current,
  valid voltages, being able to read this from data sheets, source
  vs. sink)

universality of NAND and NOR (being able to build other gates from
  either of these two)

DeMorgan's Laws (various forms of same idea)

typical logical elements (what they are, what you can do with them):
and/or/xor/not/ etc basic gates
S-R latches (built with NOR)
flip-flops (JK and D, edge triggered)
decoders (e.g., HC138)
counters (e.g., HC393)
registers (e.g., HC574)


STATE MACHINES:

understanding and creating state transition diagram
assignment of unique #s to different states
indicating transition conditions
creating state transition table from diagram
creating logic equations from table
minimizing equations
implementing equations with gates and HC574 latch


FREQUENCY/PERIOD

order-of-magnitute "everyday" examples of each of these

1 ns (nanosecond, 10^-9 sec) -> 1 GHz (gigahertz, 10^9 cycles/sec or Hz)
  --> simple HC gate delays
1 us (microsec, 10^-6 sec) -> 1 MHz (megahertz, 10^6 Hz)
  --> 68HC11 E clock rate
1 ms (millisec, 10^-3 sec) -> 1 kHz (kilohertz, 10^3 Hz)
  --> audio frequencies


HC11

register model (set of internal registers)
memory map (16 addr bits -> 65535 aka 64K of addr space, 0x0000-0x01ff
is RAM, 0x1000-103F is ctrl register bank, stack builds downward in
memory, program execution moves upwards)
control registers
addressing modes (inherent, immediate, direct (zero page, 1 byte)
extended (whole 64k range, 2 bytes) , indexed)
status reg/condition codes
 and branching
subroutines/use of stack
single-chip mode vs. expanded-mode
branch (bsr -> 1-byte relative offset) vs. jmp  (16-bit absolute value)