New Micros NMIY-0031, Manual

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2 / 2 6 / 2 0 0 2 2 : 0 6 P M 2 / 2 6 / 2 0 0 2 3 3
N M I Y - 0 0 3 1 P R O G R A M M I N G
Programming
Programmable board resources include interfaces for:
•
latched 8 bit input and 8 bit output port
•
raw (direct) 8 bit I/O port including:
•
two interrupts
•
two timer/event counters
•
4x5 keypad
•
LCD
•
serial data port
The 8031 processor has four memory mapped I/O ports; one is available to the user. Two ports
are required for bus address and data. The third port provides various signals: serial I/O, external
interrupts, timer/counter functions, and data space read/write. The fourth port is available to the
user. The eight lines of this port are available on J5.
The raw data port, interrupts, timer/counters, and serial port are implemented internally in the
8031. The other items are memory mapped to the processor externally by the board. The keypad
port is created with external logic. An additional port (latched) with eight inputs and eight
outputs is available at J4.
MEMORY
Three memory sockets are provided on the NMIY-0031. U2 is intended for the operating
system. Available items for U2 are
BASIC, FORTH
, and Monitor. A Small C compiler is also
available on diskette. Using C, the user can install an EPROM with a custom application
operating system for production. To support rapid development, electrically alterable devices
may be used in any of the three memory sockets to provide rapid development turnaround,
avoiding EPROM erase-reprogram cycling.
External memory address space on the 8031 is divided into two parts. A 64K program address
space and a 64K data address space. On the NMIY-0031 board, this distinction can be
maintained strictly by the user, or configured so that the two spaces overlap in U3.
U2 is mapped to the bottom of program memory space. For example, if an 8Kx8 EPROM is
installed then U2 is addressed from 0000 to 1FFF. Through configuration, U2 accepts up to 64K
of EPROM program space. See
Jumpers
for details.