Page 378 - Embedded Microprocessor Systems Real World Design
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schematic representation of, 213f timers, 246
semaphore use, 215-216 when to use, 251
dynamic. see DRAM Reference voltage, 103-104
estimation of, 7 Refresh cycle
ICs, 65 DRAM, 52-53
microprocessor selection and, 7 internal, 52
nonvolatile, 45, 48 microprocessor and, conflicts between,
requirements needed, 7 53
restrictions on, 137 self-refresh capability, 53
static, 45 Registers
types of, 45 for communication in multiprocessor
usage of, 7 systems, 205-21 1
RAS access time, 49 context switching, 157
RAS/CAS precharge time, 50 debugging, 193-194, 282
RAS hold time, 50 D-type, 321, 322f
-RD signal, 98 hardware debug, 258
Read modify write (rmv) cycle, 51 input capture, 113
Real-time events, 9-10 packaging of, 321
Real-time operating system saved on stack, 156
applicability of, 251 segment, 285
application using, 267-269 types of, 320-321
buffers, 243 Reloading timer, 108f, 109
challenges associated with, 251 Requirements definition
characteristics of, 237-238 description of, 3-5
communication in, 247-248, 251 example of, 2627
costs of, 251 RF energy
debugging, 252 emissions control, 87-88
description of, 130 radiated susceptibility, 89
DOS emulation, 260-261 regulations on, 86
full operating system, 238 ROM
functions supported by, 238 characteristics of, 42
hardware effects, 250 debugging information written to,
interrupts and, 247 175-1 76
kernel, 237, 251 definition of, 42
memory DOS in, 260
management of, 244-245 emulators, 193
requirements, 251 estimating requirements for, 7
microcontrollers, 252 ICs, 65
microprocessors, 10-1 1, 251-252 mask charges for producing, 13
multitasking microprocessor selection and, 7-8
definition of, 238 trace data for debugging read from,
eventdriven scheduling, 240-241 1761 77
preemptive scheduling, 239, 241, 251 ROM 8031, 13
tasks activation and deactivation, ROMability
239-240 definition of, 12
time slicing and, 238, 239f microprocessor selection and, 12-1 4
overview of, 235-238 Round-robin scheduling, 235
preemption considerations, 248-250 Row address hold time, 49
resource management, 245-246 Row address setup time, 49
scheduling in, 236 Row address strobe, 45
tasks in RTOS. see Real-time operating system
communication between, 243-244
scheduling of, 244 Scheduling, in real-time operating system
tracking of, 242 eventdriven, 240-241
Index 359