19-0313; Rev. 0; 9/94
MAX187 Evaluation System/Evaluation Kit
_______________General Description
The MAX187 evaluation system (EV system) consists of a
MAX187 evaluation kit (EV kit) board plus a Maxim
68HC16 microcontroller (µC) module. Both boards come
fully assembled and tested, and software is provided. The
unit connects to an IBM-compatible personal computer.
The EV system can function as a data acquisition system,
collecting samples from the MAX187, storing them in mem-
ory, and displaying the conversion results on the host com-
puter. Conversions may be self-timed or synchronized to
an external timebase. Waveforms can be digitized and dis-
played graphically versus time.
The EV system can also evaluate the MAX187’s shutdown
feature, and has provisions for monitoring the supply cur-
rent in the various modes of operation (internal reference,
external reference, or power-down).
Order the EV system (MAX187EVC16-DIP) for comprehen-
sive evaluation of the MAX187 or MAX189. Order the stand-
alone EV kit (MAX187EV KIT-DIP) for custom use or if the
68HC16 module (68HC16MODULE-DIP) has already been
purchased with another Maxim EV system. The MAX187
EV kit can also be used to perform limited evaluation on a
stand-alone basis (see the MAX187 EV Kit Quick Start sec-
tion). The EV system requires an external DC power source
(such as a 12V DC wall transformer) and an IBM-compati-
ble computer with a serial port and a 5 1/4" disk drive. To
evaluate the MAX189, order the MAX187EVC16-DIP plus a
free sample of the MAX189BCPA.
___________________________Features
o
Evaluates MAX187 and MAX189
o
Complete Evaluation System Includes EV Kit and
68HC16 µC Module
o
12-Bit Resolution ADC
o
QSPI Serial Interface
o
0V to 4.096V Input Range
o
Internal Reference Voltage (MAX187)
o
Low-Supply-Current Shutdown Mode
o
Complete Source Code Provided
o
Proven PC Board Layout
o
Convenient Test Points Provided on Board
o
User Prototype Area
o
Fully Assembled and Tested
Evaluates: MAX187
______________Ordering Information
PART
MAX187EVC16-DIP
MAX187EVKIT-DIP
68HC16MODULE-DIP
TEMP. RANGE
0°C to +70°C
0°C to +70°C
0°C to +70°C
BOARD TYPE
Through-Hole
Through-Hole
Through-Hole
___________________________________________________________________EV System
™
QSPI is a trademark of Motorola Corp.
________________________________________________________________ Maxim Integrated Products
1
Call toll free 1-800-998-8800 for free samples or literature.
MAX187 Evaluation System/Evaluation Kit
Evaluates: MAX187
_______EV System Component List
QTY
1
1
DESCRIPTION
MAX187 evaluation kit (MAX187EVKIT-DIP)
68HC16 µC module (68HC16MODULE-DIP)
____________EV Kit Component List
DESIGNATION
C1
C2, C3
J1
J4
JU1
R1
U1
None
None
None
QTY
1
2
1
1
1
1
1
4
1
1
DESCRIPTION
0.1µF ceramic capacitor
4.7µF electrolytic capacitors
Female 40-pin data connector
6-pin header
3-pin header
10kΩ resistor
Maxim MAX187ACPA
Rubber feet
8-pin socket for U1
MAX187 printed circuit board
__MAX187 EV System Quick Start
This section applies only to the use of the MAX187 EV
kit operating with Maxim’s 68HC16 module.
1) Copy the files from the distribution disk to your hard
drive or to blank floppy disks. Store the MAX187 EV
kit software in its own directory to prevent conflicts
with other Maxim EV kit files. The necessary files are
in the root directory of the distribution disk, and
ancillary files are located in the SOURCE and
TMS320 subdirectories. These subdirectories are
not required for EV kit operation, and are described
in other sections of this manual.
2) Carefully connect the boards by aligning the 40-pin
header of the MAX187 EV kit with the 40-pin con-
nector of the 68HC16 µC module and gently press
them together. The two boards should be flush
against one another.
3) Use a small flat-blade screwdriver to connect a 9V
to 15V DC power source to the µC module. The ter-
minal block is located next to the on/off switch, in
the upper right corner of the module. Observe the
polarity marked on the board.
4) Connect a cable from the computer’s serial port to
the µC module. If using a 9-pin serial port, use a
straight-through 9-pin female-to-male cable. If the
serial port uses a 25-pin connector, a standard 25-
pin to 9-pin adapter will be required.
5) Start up the MAX187 software on the IBM PC by set-
ting the current directory to match the directory con-
taining the Maxim programs, and then type the pro-
gram name “MAX187”.
6) The program allows the user to select which serial
port is connected to the µC module. Press the
space bar until the correct port is highlighted, then
press ENTER.
7) The MAX187 program will switch to terminal-emula-
tion mode. At this point, apply power to the 68HC16
module. The LED should light, and within 5 seconds
the program will display a logon banner. The LED is
a status indicator, not a power indicator; it will flash
to indicate module readiness. Refer to the 68HC16
module self-check system.
8) To download and run the RAM resident code on the
µC module, press ALT+L (i.e. hold down the ALT
key and strike the L key). The program prompts for
the file name. Press the ENTER key to download
and run the file KIT187.S19 on the 68HC16 module.
9) The KIT187.S19 RAM resident program offers a
menu of commands, listed in Table 1.
Stand-Alone MAX187 EV Kit
_________________________Quick Start
This section applies only to the use of the MAX187 EV
kit without the µC module.
1) Connect a regulated 5V DC power supply to the ter-
minals labeled POS5 and GND. The GND pad is
ground, and the POS5 pad is the 5V input. The
board draws less than 5mA of supply current.
2) To enable the MAX187’s internal reference, connect
the SHDN pin to 5V. To use an external reference,
leave the SHDN pin open and provide a reference
voltage at the VREF pad. To put the MAX187 in
shutdown mode, connect the SHDN pin to ground.
3) Connect the interface signals to the CS, SCK, and
DOUT test points. Use the AGND test point as sig-
nal ground. See the MAX187 data sheet for timing
information.
4) Apply the input voltage to the terminals labeled
INPUT and GND.
2
_______________________________________________________________________________________
MAX187 Evaluation System/Evaluation Kit
________________Detailed
Description
__________________________of Software
EPROM Resident Program
A small bootstrap program is stored in the EPROM
located on the 68HC16 board. The EPROM resident
program initializes the 68HC16, tests the static RAM,
configures the chip-select logic, establishes serial com-
munications with the host, and downloads a program
into RAM. It starts operating on power-up or whenever
the RESET button is pressed. After RESET, it tests the
RAM and then waits to receive a character on its serial
port before transmitting its identification banner.
Personal Computer Program
MAX187.EXE, which runs on an IBM-compatible comput-
er, is a terminal program that establishes communication
with the 68HC16 module and allows the user to down-
load and run a Maxim-provided RAM resident program.
The serial communication baud rate is initiated at 1200
baud to ensure proper operation with slower systems.
The MAX187.EXE program provides several commands
that are associated with the host computer. These func-
tions are listed in Table 3.
The MAX187.EXE program can store the text of a termi-
nal session in a log file. To begin recording the terminal
session, press ALT+O [the letter O]. The program will
ask for a file name. Press ENTER to accept the default
file name, or type in a different name. If there is already
a file with that name, the old file will be erased. To close
the file, press ALT+C. The log file will contain the com-
plete text of the terminal session from the time when the
file is opened until the file is closed.
Evaluates: MAX187
RAM Resident Program
KIT187.S19 and MIN187.S19 are 68HC16 RAM-resident
programs that are transferred from disk to the static RAM
on the 68HC16 module. They are used transparently by
the example programs. The example programs that do
not require the full command set of KIT187 download the
MIN187 program, which is smaller and implements only
the read and collect commands. Because the MIN187
occupies less user RAM, more sample data can be col-
lected (MIN187 can collect approximately 400 more
samples than KIT187 before it must upload the samples
to the host.) When the KIT187 program is running, it
offers the commands listed in Table 1. The MIN187 pro-
gram commands are listed in Table 2.
Graphing Program
The program SAMPL187.BAS samples the MAX187
and draws a graph of voltage over time. Preset sample
rates range from 2.5ksps to 10ksps. The time base is
approximate and there is no triggering mechanism, so
this program is only suitable for observing the wave-
forms of an external frequency generator.
Table 1. Commands Available when
KIT187.S19 is Running
KEY
Space
V
R
O
S
L
D
T
M
?
FUNCTION
Read the MAX187 and print result in decimal.
Repeatedly read the MAX187 and print result in
decimal.
Read the MAX187 and print result in hexadecimal.
Oscilloscope test; observe system timing by operat-
ing the MAX187 at high speed without processing
the data.
Set the state of the SHDN pin.
Display low-power menu.
Set power-up delay and sleep time
(low-power menu only).
Test the accuracy using the current power-up delay
and sleep time settings (low-power menu only).
Return to main menu (low-power menu only).
List the available commands.
Table 2. Commands Available after
MIN187 has been Downloaded
KEY
?
r
FUNCTION
Print RAM resident program version and list of com-
mands available.
Read the MAX187 and display the value as a 2-byte
hexadecimal number.
Collect and upload a number of data samples to the
host PC. Samples can be collected at full speed, or
collected with a fixed delay, or collected in accor-
dance with an external clock. Approximately 16,000
samples may be collected and they can be dis-
played in either decimal or in hexadecimal.
Exit the evaluation software.
c
ESC
_______________________________________________________________________________________
3
MAX187 Evaluation System/Evaluation Kit
Evaluates: MAX187
Table 3. Commands Available in
MAX187.EXE Terminal Program
KEY
ALT+L
ALT+X
ALT+P
ALT+R
ALT+O
ALT+C
ALT+B
ALT+1
ALT+4
ALT+9
ALT+2
Exit to DOS.
Change port (COM1, COM2).
Send RESET command to 68HC16.
Open a log file.
Close the log file.
Display baud rate menu.
1200 baud
4800 baud
9600 baud
19200 baud
FUNCTION
Load and run resident code on 68HC16.
68HC16
I/O
PCS0
SCK
MISO
MAX187
SHDN
CS
SCLK
DOUT
Figure 1. QSPI Interface Schematic
Programming Languages Used
The IBM PC programs were compiled under Borland
C++ version 3.1. The EPROM and RAM resident
68HC16 programs were assembled using the Motorola
68HC macro assembler version 4.1, which comes with
Motorola’s 68HC16Z1EVB evaluation board. Contact the
Motorola Microprocessor and Memory Technologies
Group at (512) 891-2628.
The BASIC programs are written in Mircosoft QuickBasic
1.0, which comes with MS-DOS 5.0 and later versions.
Table 4. Compiled Program Dependencies
PROGRAM
PROGRAM SECTION
main program
68HC16 command
SIMPLE.EXE
interface
MAX187 EV kit commands
main program
custom controls
MAX187.EXE terminal + downloader
SOURCE FILES
simple.c
sercmd.c, sercmd.h
max187.c, max187.h
shell.cpp, global.h
meters.cpp, meters.hpp
download.cpp,
download.h
Using the QSPI to Read the MAX187
The 68HC16 module uses its queued serial peripheral
interface (QSPI) in master mode to read the MAX187
between conversions. Figure 1 shows the schematic of
the QSPI interface connections. The MAX187 EV kit soft-
ware uses the following algorithm (provided on disk in the
SOURCE subdirectory, file MIN187.ASM):
1) Initialize QSPI parameters as follows:
Master Mode
SPBR = 2 (4.192MHz serial clock)
CPOL = 0, CPHA = 1
BITS = 13 bits per transfer
DTL = 1 (1.9µs delay after transfer)
(DSCKL is not used)
Control RAM entry must enable BITS and DTL;
CS = 0 when active.
2) Assert CS low.
3) Wait 8.5µs (maximum conversion time for the
MAX187) or until MISO goes high. (Since DSCKL is
only 7 bits, the maximum delay-before-clock available
for a 16.78MHz 68HC16 is 128/16.78MHz = 7.628µs.
Thus, the QSPI’s DSCKL parameter cannot be used
unless the system clock frequency is reduced.)
4) Start QSPI transfer.
5) Wait until QSPI transfer is complete.
68HC16 command
sercmd.c, sercmd.h
interface
MAX187 EV kit commands max187.c, max187.h
DOS Development Platform
For applications that require custom software, the MAX187
EV kit includes a set of programs that can be used as a
development platform to extend the functionality of the
basic kit. Source code is in the SOURCE subdirectory of
the MAX187 EV kit disk. Advanced C or C++ program-
mers should see Table 4 for the makefile dependencies.
The simplest program that accesses the MAX187 EV kit is
SIMPLE.EXE, which loads the small RAM resident pro-
gram into the 68HC16 module and then performs continu-
ous conversions, until the user presses a key.
To run the SIMPLE.EXE program, enter the command SIM-
PLE from the DOS prompt. The program will ask which seri-
al port is connected to the µC module. Press the ‘1’ number
key to select COM1, or press the ‘2’ number key to select
COM2. To terminate the program, press the ESC key.
4
_______________________________________________________________________________________
MAX187 Evaluation System/Evaluation Kit
Evaluates: MAX187
Listing 1. Using the QSPI to Read the MAX187
_______________________________________________________________________________________
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