Section 5. Circuit Description; Introduction; General Circuit Description; Detailed Circuit Description - Data I/O 298 Manual

SECTION 5
CIRCUIT DESCRIPTION
5.1 INTRODUCTION
This section describes the 298 Universal Programmer's
circuitry. It includes both a general and detailed description
and of the programmer's main circuitry functions. Each
detailed circuitry function is described in its own subsection
along with a biock diagram.
This section also discusses the main components of the
298 programmer, address map assigments, and assembly
cabling.
5.2 GENERAL CIRCUIT DESCRIPTION
The 298 is a microprocessor-based programmer utilizing
bus-style architecture. Figure 5-1 shows the functional
blocks of each of the circuits in the 298. These circuits are
described in the following paragraphs.
AC line voltage passes through a voltage selector and filter
to the transformer and a cooling fan. The AC is rectified
filtered and regulated for use by all other circuits on the '
298.
A microprocessor unit (MPU) controls all operations for the
298. MPU circuits are interfaced to a keyboard and display.
An RS232 serial port is standard.
A.C.
The .actuai programming of devices is performed through a
64-pm connector (J7lwhich interfaces with programming
modules or Pa ks, Optionally, devices can be oroarammed
by a PROM Handler through a special
hardw~r~ lnterfa~e
provided for this purpose.
The internal RAM of the 298 prnvides stoiage for all
programming data information whether from a master
device or from an external source (computer, terminal,
etc.).
5.3 DETAILED CIRCUIT DESCRIPTION
Figure 5-2 shows an interconnect diagram of the 298. Each
of the circuit areas, power supplies, MPU,
keyboard/display, RAM, and interface circuits, are
described in the following paragraphs and shown in
separate block diagrams.
Figure 5-2 also shows the cabling between assemblies
along with associated connector cables and part numbers.
The schematic for each board is located in Appendix F.
The component layout of the 298 is
shOV'.'n
in figure 5-3.
1-----,
KEYBOARD/DISPLAY
LINE POWER
SUPPLY
FAN
RS232 S
-
" '7'
_f
~l
+
ERIAL 1/0
1
CONTROLLER
RAM
.- ....
L
J
J7
l
INTERFACE TO
PROGRAMMING MODULE
OR PAK
INTERFACE TO
i-.
...
HANDLER
.......
,
(OPTION)
EXPANSION
--
- r
RAM
Figure 5-1. Functional Diagram of 298 Universal Programmer
5-1
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