IC89E54 Datasheet, PDF (7/36 Pages) Integrated Circuit Solution Inc – 8-BITS SINGLE MICROCONTROLLER with 16/32/64-Kbytes of FLASH, 256 byte +512 byte RAM

IC89E54/58/64
Table 1. Detailed Pin Description (continued)
Symbol
PSEN
PDIP
29
PLCC
32
PQFP I/O
26
O
ALE/PROG 30
33
27 I/O
EA/VPP
31
35
29
I
Vss
20
22
16
Vcc
40
44
38
I
Name and Function
Program Store Enable: The read strobe to external program
memory. When the device is executing code from the external
program memory, PSEN is activated twice each machine cycle
except that two PSEN activations are skipped during each
access to external data memory. PSEN is not activated during
fetches from internal program memory.
PSEN is an input control signal while memory program and
verification.
Address Latch Enable: Output pulse for latching the low byte
of the address during an address to the external memory. In
normal operation, ALE is emitted at a constant rate of 1/6 the
oscillator frequency, and can be used for external timing or
clocking. Note that one ALE pulse is skipped during each
access to external data memory.
This pin is also the program pulse input (PROG) during pro-
grammable memory programming and erase.
External access enable: EA must be externally held low to
enable the device to fetch code from external program memory
locations 0000H to FFFFH. If EA is held high, the device
executes from internal program memory unless the program
counter contains an address grater than 3FFFH/7FFFH re-
specting to IC89C54/58 and the device always executes inter-
nal program memory in IC89C64.
This is also receives the 12 V programming enable voltage
(Vpp) during Flash programming, when 12 V programming is
selected.
Ground: 0V reference.
Power Supply: This is the power supply voltage for operation.
OPERATING DESCRIPTION
The detail description of the IC89E54/58/64 included in this
description are:
• Memory Map and Registers
• Timer/Counters
• Serial Interface
• Interrupt System
• Other Information
• Flash Memory
MEMORY MAP AND REGISTERS
Program Memory and data memory
Table 2 shows program memory and data memory size
versus three products. The IC89E54/58/64 series includes
a standard IC80C32 and a 16K/32K/64K Flash Memory. The
IC89E54/58/64 includes IC80C32, a 16K/32K/64K Flash
and some enhanced functions. The figures 3~5 show
IC89E54/58/64 program memory architecture and program
memory access status versus EA pin. These enhanced
functions are described in later descriptions. The program
memory and data memory access ranges are listed table 1.
The AUX RAM status is disable after reset, so MOVX
instructions will access external RAM. If set ENARAM bit,
the AUX RAM will be enabled and MOVX instructions will
access AUX RAM in 0000H~01FFH, access external RAM
in 0200H~FFFFH. Figure 6 shows the external data memory
and AUX RAM accesses relation.
Integrated C ircuitSolution Inc.
7
MC012-0C 11/16/2001