FONIX FP40 / FP35 / 7000
Communications Troubleshooting Guidelines

04/04/97

You should use these guidelines if you are having problems getting your FONIX hearing aid analyzer to communicate with your host computer. If you are trying to install an RS232 option upgrade, refer to the document titled "RS232 Installation Instructions".

The most common problems encountered by Frye support personnel are listed below. It is always best to troubleshoot the most common causes first, before moving on to more complicated causes. For example, if you had the RS232 option installed at the factory, you should start out with the assumption that it has been installed correctly and troubleshoot problems external to the analyzer first.

Most common RS232 problems encountered:

  • Customer didn't purchase RS232 but thought they had the option.
  • Bad RS232 cable
  • Customer had RS232 cable connected to computer COM port 2 and was trying to communicate with software which was using COM port 1 (or vice versa).
  • Customer had multiple COM ports in computer, but they were not configured properly on the serial card (e.g. COM ports were not enabled, interrupts conflicted, etc.)
  • Customer installed RS232 option in the instrument but did something wrong during the installtion.
  • Using the Frye RS232 cable (with the leds) with some laptops may not work because the laptop does not provide true RS232 output levels.

To help you troubleshoot the RS232 operation of your FONIX instrument and RS232 software, Frye now supplies the following items with the analyzers which have the RS232 option and with the RS232 option upgrades:

  • Special RS232 cable with red/green diagnostic LEDs
  • Diagnostic software to check the computer's serial port

If you purchased your RS232 option before these items became available and you are having trouble with your RS232 operation, you should contact Frye to obtain these troubleshooting tools.

TROUBLESHOOTING PROCEDURE

1. Check the analyzer's RS232 option

When you turn on your analyzer, it checks for RS232 software on the system software EPROM. If it detects the software, it performs a limited self-test of its RS232 hardware. A status message is displayed below the Frye Electronics copyright notice on the opening display screen. This message can be any of the following:

  • <no message>—No RS232 software was detected.

This could also indicate bad system software EPROMs, but this is unlikely if the instrument is operating normally in all other functions. Contact Frye to verify that you have the RS232 option or to get replacement EPROMs. Have your serial number handy.

  • RS-232 AVAILABLE -- RS232 software was detected and limited RS232 diagnostics were passed.
  • RS-232 BAD UART -- RS232 software was detected, but the hardware is bad.

If your RS232 option was factory installed, contact Frye. Refer to the RS232 installation instructions for more information.

Note: Some laptops do not provide a full RS232 compatible output. This may cause a problem if you are using the Frye supplied RS232 cable with the red and green leds. If you are using a laptop, try replacing the Frye supplied cable with a standard RS232 cable (without the leds).

2. Check that the analyzer is sending polls

When the analyzer is ready to accept commands from the computer it sends a stream of special data packets, called "polls", to the computer. To determine if the analyzer is sending polls, connect the Frye RS232 cable with the red and green LEDs between the analyzer and the computer (the LEDs go on the computer end) and reset the analyzer. Run the FCHECK program on the computer. Refer to the FCHECK documentation for more information on the use of the FCHECK program.

The analyzer will come up with the opening logo screen and begin sending polls. You should see a flickering red LED on the RS232 cable to indicate that polls are being sent down the cable. If you do not see the red LED flickering, there may be a problem with your analyzer (or your test cable is bad). Note: If the FRYERS driver has not been run on the computer, or the FCHECK program is not running, you may not see the red led flashing. The FP40 requires that a program is running on the PC that enables the RS232 operation before it will send polls.

If you do not have the Frye cable, but you have an oscilloscope or VOM handy, you can use the scope or meter to look for pulses on pin 3 of the 25-pin connector or pin 2 of the 9-pin connector.

If your analyzer is sending polls and you are not communicating, you can assume the analyzer is functioning properly and look for problems in the cable or computer.

If you do not have a computer handy, or you are uncertain if the computer is setup properly, you can "fake" the FP40 into thinking that the RS232 has been enabled by shorting pins 4 and 5 on the 25 pin connector, or pins 7 and 8 on the 9 pin connector. This will enable the FP40's RS232 interface and should cause the red led to start flashing.

3. Check the RS232 cabling

A bad RS232 cable is often the cause of communication problems between an analyzer and computer, particularly if the problem seems to be intermittent. The quickest way to check for a bad cable is to try a known good cable. If you don't have a cable that you are sure is good, you may want to purchase a new one. The odds of the new cable being bad are slight, so if you still have the problem after trying a new cable, you can assume that the problem is in the computer or application software.

The FONIX RS232 option expects a standard 'straight-thru' RS232 cable. These cables are available from most stores that carry computer supplies. If you want to use a longer cable, the RS232 standard supports cable lengths up to 50 feet at the communication rate used by FONIX instruments, but you can probably go up to 100 feet without having any problems. Do not use RS232 cables which are designated as "Null Modem" cables. Your computer's serial port connector may be either a 9-pin or 25-pin connector (or you may have both types). You may connect your analyzer to either of these ports. You may use a standard 25-pin-to-9-pin adapter to adapt the Frye RS232 cable (or any other standard RS232 cable) to use the 9-pin port.

4. Check the computer's serial port

Most computers have one 25-pin female parallel port and one or two male 25-pin or 9-pin serial ports. With few exceptions you can identify the serial ports by looking for 25-pin or 9-pin connectors on the back of your computer which are male (they have pins sticking out). The serial card(s) in your machine usually have jumpers which disable or enable these ports and jumpers to determine which connector gets assigned to which communications port: COM1, COM2, COM3, or COM4. If you have two COM ports, they are almost always configured as COM1 and COM2 at the factory or at the computer store.

It is important for you to determine which COM port has been assigned to each connector so that you are not trying to communicate with COM1 when you are connected to COM2. Some computers have these ports labeled, but most don't. You can usually look at your computer documentation or the documentation that came with your serial cards to determine this information, but often it is easier to just run some program which uses the serial ports and figure out which port works when you have the software configured for that port. This is the approach we have taken with the RS232 diagnostic program.

The diagnostic program called FCHECK checks several functions of your RS232 communication from the computer side. To use FCHECK, you should have your computer and analyzer connected with an RS232 cable. Reset your analyzer so it is in the opening screen.

When FCHECK starts, the Status box in the upper right hand corner will display the message "-- Testing --". Eventually this status box will display either the message "No Poll" or the message "Test Completed".

A "No Poll" message indicates that the computer is not receiving polls from the analyzer on COM1. The Help window describes error conditions that might be causing the problem.

A "Test Completed" status message should be accompanied by a message in the Help window saying that RS232 communication on COM1 is functioning successfully. If you get this message, then you have a functioning communications link via the FRYERS protocol between the analyzer and the computer. If your application still isn't working, you probably have an error in your application. If your application can be configured to use COM1 or COM2, such as the Frye CHAP program, you should check to make sure that the program is configured for the correct port.

If you receive a 'No Poll' on COM1, press '2' to begin testing COM2. Do not change the connection on the back of your computer. If you get a successful connection, you know that the connector you are currently connected to on the back of the computer is COM2. If you get a 'No Poll' on COM2 as well, you know that the port is disabled, or malfunctioning, or is configured as COM3 or COM4. To test for COM3, press "3". To test for COM4, press "4". If you cannot get a successful communication using FCHECK, then you most likely have a malfunctioning or incorrectly configured serial card.

5. If you have performed all the checks in steps 1 through 4 and still cannot get the computer to communicate with your analyzer, call Frye for additional help.

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