Spectrum Software
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Spectrum Software has released Micro-Cap 11, the eleventh generation of our SPICE circuit simulator.

For users of previous Micro-Cap versions, check out the new features available in the latest version. For those of you who are new to Micro-Cap, take our features tour to see what Micro-Cap has to offer.




HP Printer Driver Incompatibilities


An incompatibility brought to our attention recently by one user occurs between the new HP printer drivers and the Sentinel security key. These drivers use nonstandard bidirectional communication which can cause trouble to other devices that are present on the parallel port. Rainbow, the manufacturer of the security keys, provided us with some solutions for this occurrence in one of their technical notes.

If you have multiple parallel ports:
The easy solution to this problem is to place the security key on a different parallel port that the HP driver is not accessing.

If you have a single parallel port:
The most obvious solution is to change the printer driver. An older HP compatible version of the driver should work with the key. If you are using the HP5L printer, there is a PCL version of the driver available on the install disk. Custom installation must be selected during the install process to access this driver. Other HP printers may have similar solutions.

For HP Deskjet Printers:
The following steps may be used to disable the bidirectional communication mode in the HP Deskjet 855c, 850, 680c, 660, and 540 drivers.

1) Exit from all Windows applications.

2) Choose Run from the File menu in the Program Manager.

3) In the Run dialog box type the following appropriate command line:

HPVCNFIG ;   for HP 850, 855c, 660c printers
HPRCFG01 ;   for new HP 850 and 855c printers
HPFCFG02 ;   for new HP 660c printers
HPFCFG01 ;   for HP 660c-SE printers
HPVCNFIG ;   for HP 540 printers

4) Click OK, and then click Continue when a message appears that says the program will modify the System.ini file.

5) The following selections should be changed in the dialog box that appears:

For HP 850 and 660 printers:
A) Disable the "print cartridge query".
B) Disable the "bidirectional communication".

For HP 540 printers:
A) Enable the "reverse channel".
B) Enable the "simple IOD".

6) Restart Windows.

7) From the Main group, choose Control Panel and then Printers. Click on the Connect command button. Highlight the LPT1.DOS port and then disable the "fast printing direct to port" in the lower left hand corner. Close the dialog box.

If your printer is printing garbage with the key attached, disabling the "fast printing direct to port" off in Windows will sometimes help.

In the extreme case, where none of this helps, and for some reason, you must use the newest printer driver, the only alternative is to install a new parallel port.

For additional information, you should contact HP support.
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