EMS6500 EM Microelectronic, EMS6500 Datasheet - Page 40

• Manufacturer Part Number: EMS6500
• Description: Microcontroller Development System 4-bit (Emmon), Simulators 4-bit
• Manufacturer: EM Microelectronic

3.
Copyright  2003, EM Microelectronic-Marin SA
3.1.
EM66xx Programming Model
This section provides an overview of the EM66xx 4-bit microcontroller family and the
corresponding programming model. For a more detailed description of each
controller please refer to the corresponding specifications.
The general structure of the EM66xx family of microcontrollers is shown below.
At the heart of the EM EM66xx microcontroller family is a 4-bit arithmetic and logic
unit (ALU), which is capable of executing 32 different instructions. The ROM
memory used has a maximum capacity of 4K 16-bit instructions. The data consists
of 126 4 bit words which is distributed between the RAM and peripheral registers.
The entire address space can be accessed in an indexed manner using the register
Global Architecture
3 * PC<12>
Stack Pointer
Control Unit
Branch Address
MAC<4> Cy, Cy_int,Z
ALU<4>
Fig. 24 General structure of EM66xx 4bit microcontrollers
SAC<4>
A Bus <4>
Op-code
B Bus <4>
ROM
(Max 4K * 16)
32
RAM and
IO Ports
(Max 126*4)
Development System
IR
MUX
XH
XL
RAM(i) <7>
CALL to Interrupt
address
Data <4>
www.emmicroelectronic.com
EM66xx
Binder 4.3-01/03 Rev. B/495