FMS7401LEN Fairchild Semiconductor, FMS7401LEN Datasheet - Page 46

• Manufacturer Part Number: FMS7401LEN
• Description: IC CTRLR POWER DGTL EEPROM 8DIP
• Manufacturer: Fairchild Semiconductor

Specifications of FMS7401LEN

• Applications: Digital Power Controller
• Core Processor: 8-Bit
• Program Memory Type: EEPROM (1 kB)
• Ram Size: 64 x 8
• Number Of I /o: 6
• Voltage - Supply: 2.7 V ~ 3.6 V
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Through Hole
• Package / Case: 8-DIP (0.300", 7.62mm)
• Mounting Style: Through Hole
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Interface: -
• Controller Series: -
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant
• Other names: FMS7401LEN_NL; FMS7401LEN_NL

10 8-Bit Microcontroller Core
The FMS7401L’s 8-bit microcontroller core is specifically designed for low cost applications involving bit manipulation, shift-
ing and block encryption. It is based on a modified Harvard architecture meaning peripheral, I/O and RAM locations are
addressed separately from instruction data.
The core differs from the traditional Harvard architecture by aligning the data and instruction memory sequentially. This
allows the X-pointer (11-bits) to point to any memory location in either segment of the memory map. This modification
improves the overall code efficiency of the microcontroller core and takes advantage of the flexibility found on the von Neu-
mann architecture and stored program concept.
10.1 Core Registers
The microcontroller core has five general-purpose registers. These registers are the Accumulator (A), X-Pointer (X), Program
Counter (PC), Stack Pointer (SP) and Status Register (SR). The X, SP and SR registers are memory mapped while A and PC
are not.
REV. 1.0.3 1/24/05
PRODUCT SPECIFICATION
A
X
PC
SP
SR
10
9
R
7
0 0
Figure 16. Core Program Model
G
Z
C
3
H
N
0
0
0
0
8-bit accumulator register
11-bit X pointer register
10-bit program counter
4-bit stack pointer
8-bit status register
NEGATIVE flag
HALF CARRY flag
CARRY flag
ZERO flag
GLOBAL INTERRUPT enable
READY flag
FMS7401L
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