MAX155EVKIT-DIP Maxim Integrated, MAX155EVKIT-DIP Datasheet - Page 7

• Manufacturer Part Number: MAX155EVKIT-DIP
• Description: Data Conversion IC Development Tools Evaluation Kit for the MAX155
• Manufacturer: Maxim Integrated
• Series: MAX155, MAX156r

both files by entering PRINT README and PRINT
MAX155EV.doc. Either file can also be examined or
printed using a word processing program.
After reading the MAX155EV.doc file, type MAX155EV to
start the program. Set the program to the port to which
the board is connected (COM1 or COM2). With the
board connected, turn on the board power. The program
displays the status of the communications link between
the system and the board. If the status does not indicate
READY, see the Troubleshooting Guide section.
Many different input configurations are possible for the
MAX155's analog inputs. Consult the MAX155 data
sheet for full details.
Apply the input levels to the eight inputs and use the
software to configure the input multiplexer as desired.
Enter a number (0–7) to select an input, then enter the
command for the proper mode.
Read the MAX155EV.doc file for full information about
program commands. Table 2 lists the available com-
mands.
The following is a checklist to help isolate problems on
the MAX155 EV kit board. It is recommended that each
step be done in the order given. Do not proceed until
each fault has been corrected. If the MAX155 EV pro-
gram indicates that the board status is READY, but the
conversions are erroneous, go to the following Analog
Section.
Is the +5V okay?
Is the input voltage (pin 8) between 5.5V and 11.5V?
Does the reset operate correctly?
Check the MAX667 output. Is the voltage on pin 2
between 4.8V and 5.2V? Go to next section if okay.
If yes, the MAX667 may be damaged. Make sure all
components are inserted correctly and no shorts
exist. If not, input source is not connected or not
functioning. D1 could also be installed incorrectly.
The RESET line (pin 16 of the MAX696) should be
high for 50ms after power-up (or whenever J1 is
momentarily shorted), then go low. If not, make sure
J1 is open and the MAX696 is correctly installed and
undamaged.
_______________________________________________________________________________________
Troubleshooting Guide
Digital Section
Microprocessor
Power
MAX155 Evaluation Kit
Is the 80C32’s clock running?
Does the 80C32 access the ROM?
Does the board transmit a stream of A5(hex) characters
after a reset?
If all of the above are operating correctly, the next step
is to verify the connection to the PC. The MAX155 EV
program can be placed in an echo mode of sending
characters typed on the keyboard and displaying those
received from the COM port. Make sure the cable is
connected to the proper serial port and to the board.
Start the MAX155 EV program and type ^Q (Ctrl Q) to
set echo mode. Each character typed on the keyboard
should now be displayed on the screen. If not, perform
the following checks:
Use a scope to check pin 19 of the 80C32. The
11.059MHz should appear distorted but present. If
not, the crystal or the 80C32 might be damaged.
Use the scope to check pin 40 of the 80C32 (the
A0/D0 signal). It this signal does not toggle every
microsecond, one of the following devices may be at
fault:
*IC8 AND IC9 CAN BE REMOVED FOR DEBUG-
GING.
Disconnect the cable to the PC and reset board. Then
use a scope to look at pin 2 of the D9 connector.
Normally, the output is at -10V. Every 280ms, a
stream of bits lasting 3ms is transmitted. The voltage
swings from -10V to +10V.
If okay, go to the next step.
If the output is stuck at +10V or -10V, check the
input of the MAX233 (pin 2). If it is an inverted 0 to
5V copy of the above, the MAX233 is okay, and the
ROM or the 80C32 is at fault.
Does pin 5 of the MAX233 swing greater than -5V to
+5V whenever a character is entered? If not, the
correct port is not selected or present. Try again
with the other port.
IC3
IC4
IC5
IC6
IC7
IC8
IC9
80C32
74HCT573
74HCT08
74HCT139
27C64
6264
74HCT245
controller
address latch
part of address decode
part of address decode
ROM
RAM*
data-bus buffer
Terminal Connection
7