Intel 8XC251SA, 8XC251SP, 8XC251SQ, 8XC251SB, Embedded Microcontroller manual Index-2

8XC251SA, SB, SP, SQ USER’S MANUAL

CJNE instruction, A-25 Clock, 2-6

external, 11-4, 11-5 external source, 11-3

idle and powerdown modes, 12-5 idle mode, 12-4

powerdown mode, 12-5, 12-6 sources, 11-3

CLR instruction, 5-9, 5-11, A-17, A-23 CMOD, 3-17, 3-19, 9-13, C-2, C-5, C-11

interrupts, 6-5

CMP instruction, 5-8, 5-14, A-15 Code constants, 4-16

Code fetches

external, 13-1, 13-5 internal, 13-5

page hit and page miss, 13-6 page mode, 13-6

Code memory

MCS 51 architecture, 3-3

See also On-chip code memory, External code memory

Compatibility (MCS 251 and MCS 51 architectures), 2-1, 3-2–3-5

address spaces, 3-2, 3-4 external memory, 3-5 instruction set, 5-1 SFR space, 3-5

See also Binary and source modes CompuServe, 1-7

Configuration

external memory, 4-8 overview, 4-1

wait states, 4-1–4-2 Configuration array, 4-1–4-4

on-chip, 4-2 Configuration bits, 4-4–4-6

UCON bit, 4-4 Configuration bytes, 4-1

bus cycles, 13-15

programming and verifying, 14-1 UCONFIG0 (table), 4-6 UCONFIG1 (table), 4-7

Control instructions, 5-1, 5-12–5-16 addressing modes, 5-12, 5-13 table of, A-24

Core, 2-4

SFRs, 3-18, C-3

Index-2

CPL instruction, 5-9, 5-11, A-17, A-23 CPU, 2-5

block diagram, 2-5 Crystal

for on-chip oscillator, 11-3 CY flag, 5-18, 5-19, C-20

D

DA instruction, A-16

Data instructions, 5-1, 5-4–5-10 addressing modes, 5-4

Data pointer, See DPH, DPL, DPTR, DPX, DPXL Data transfer instructions, 5-10

table of, A-22

See also Move instructions

Data types, 5-2

Datasheets

on WWW, 1-7

DEC instruction, 5-8, A-16 Destination register, 5-3 Device

signal descriptions, B-3 dir16, A-3

dir8, A-3

Direct addressing, 5-4

in control instructions, 5-13 Displacement addressing, 5-4, 5-8 DIV instruction, 5-9, A-16 Division, 5-9

DJNZ instruction, A-25 Documents

ordering, 1-7 related, 1-5

DPH, DPL, 3-15, C-12

as SFRs, 3-17, 3-18, C-2, C-3 DPTR, 3-15

in jump instruction, 5-13 DPX, 3-5, 3-13, 3-15, 5-4 DPXL, 3-15, C-13

as SFR, 3-17, 3-18, C-2, C-3

external data memory mapping, 3-5, 5-4, 5-10 reset value, 3-5

E

EA#, 3-8 description, 13-2

ECALL instruction, 5-15, A-24