EF6805U3 Datasheet, PDF (1/31 Pages) STMicroelectronics – 8-BIT MICROCOMPUTER UNIT

EF6805U3
8-BIT MICROCOMPUTER UNIT
HARDWARE FEATURES
. 32 TTL/CMOS COMPATIBLE I/O LINES
. 24 BIDIRECTIONAL (8 lines are LED compati-
ble)
. 8 INPUT-ONLY
. 3776 BYTES OF USER ROM
. 112 BYTES OF RAM
. SELF-CHECK MODE
. ZERO-CROSSING DETECT/INTERRUPT
. INTERNAL 8-BIT TIMER WITH 7-BIT SOFT-
. ^{WARE PROGRAMMABLE PRESCALER AND}
CLOCK SOURCE
5V SINGLE SUPPLY
..SOFTWARE FEATURES
10 POWERFUL ADDRESSING MODES
BYTE EFFICIENT INSTRUCTION SET WITH
TRUE BIT MANIPULATION, BIT TEST, AND
BRANCH INSTRUCTIONS
. SINGLE INSTRUCTION MEMORY EXA-
MINE/CHANGE
. POWERFUL INDEXED ADDRESSING FOR
TABLES
. FULL SET OF CONDITIONAL BRANCHES
. MEMORY USABLE AS REGISTER/FLAGS
. COMPLETE DEVELOPMENT SYSTEM SUP-
PORT ON INICE
USER SELECTABLE OPTIONS
. 8 BIDIRECTIONAL I/O LINES WITH TTL OR
TTL/CMOS INTERFACE OPTION
. 8 BIDIRECTIONAL I/O LINES WITH TTL OR O-
PEN-DRAIN INTERFACE OPTION
. CRYSTAL OR LOW-COST RESISTOR OSCIL-
LATOR OPTION
. LOW VOLTAGE INHIBIT OPTION
. VECTORED INTERRUPTS : TIMER, SOFT-
WARE, AND EXTERNAL
. USER CALLABLE SELF-CHECK SUBROU-
TINES
D ESCR I PTI O N
The EF6805U3 Microcomputer Unit (MCU) is a
member of the 6805 Family of low-cost single-chip
Microcomputers. The 8-bit microcomputer contains
a CPU, on-chip CLOCK, ROM, RAM, I/O, and TI-
MER. It is designed for the user who needs an eco-
nomical microcomputer with the proven capabilities
of the 6800-based instruction set. A comparison of
the key features of several members of the 6805 Fa-
mily of Microcomputers is shown at the end of this
data sheet. The following are some of the hardware
and software highlights of the EF6805U3 MCU.
1
P
(PDIP40)
FN
(PLCC 44)
PIN CONNECTIONS
March 1989
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