User`s manual

OP7100 Troubleshooting
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Dynamic C Will Not Start
In most situations, when Dynamic C will not start, an error message
announcing a communication failure will be displayed. The following list
describes situations causing an error message and possible resolutions.
• Wrong Communication Mode — Both sides must be talking RS-232.
• Wrong COM Port — A PC generally has two serial ports, COM1 and
COM2. Specify the one being used in the Dynamic C “Target Setup”
menu. Use trial and error, if necessary.
• Wrong Operating Mode — Communication with Dynamic C will be
lost when the OP7100 is configured for standalone operation. Make
sure pins 1–2 on header J4 are connected to reconfigure the board for
programming mode as described in Chapter 2, “Getting Started.”
If all else fails, connect the serial cable to the OP7100 after power up. If
the PC’s RS-232 port supplies a large current (most commonly on portable
and industrial PCs), some RS-232 level converter ICs go into a nonde-
structive latch-up. Connect the RS-232 cable after power up to eliminate
this problem.
Dynamic C Loses Serial Link
If the application disables interrupts for a period greater than 50 ms,
Dynamic C will lose its serial link with the application. Make sure that
interrupts are not disabled for a period greater than 50 ms.
OP7100 Repeatedly Resets
The OP7100 resets every 1.0 second if the watchdog timer is not “hit.” If a
program does not “hit” the watchdog timer, then the program will have
trouble running in standalone mode. To “hit” the watchdog, make a call to
the Dynamic C library function hitwd.