TECHNICAL INFORMATION DOCUMENT TITLE: PTF151 - Parallel Port Driver Update DOCUMENT ID: TID021400 DOCUMENT REVISION: D DATE: 25JAN95 ALERT STATUS: Yellow INFORMATION TYPE: Symptom Solution README FOR: PTF151 PRODUCT and VERSION: UnixWare 1.1 ABSTRACT: This patch corrects a problem in the parallel port driver that results in extremely slow printing on some very high speed printers. The updated driver corrects this problem by enabling the parallel port for interrupts at the same time a character is presented to the printer. This PTF requires UnixWare v1.1.1. This version has been re-released. ADDITIONAL CONFIGURATION This problem is known to occur on HPIIIsi printer connected to local parallel port. Other: SYMPTOM Extremely slow printing on local parallel printer. SOLUTION Apply the ptf151 file. Installation Instructions: DATATYPE: datastream 1. Download the ptf151.Z and ptf151.txt files to the /tmp directory on your machine. 2. Read the release notes contained in the ptf151.txt file. 3. Now become root, uncompress the file and add the package to your system using the following commands: $ su # uncompress /tmp/ptf151.Z # pkgadd -d /tmp/ptf151 ptf151 Solution Specifics RELEASE NOTES These release notes acquaint you with the contents of UnixWare PTF151 - Parallel Port Driver Update 1. General Description This patch corrects a problem in the parallel port driver that results in extremely slow printing on some very high speed printers. The problem was caused by a 10-microsecond delay between presenting a character to the printer and enabling the parallel port for interrupts. If the printer acknowledged the character during this interval, the parallel port would ignore the acknowledge signal (ie, would not generate an interrupt). Any subsequent character would then be presented to the printer only after a 2-second timeout had occurred. The updated driver corrects this problem by enabling the parallel port for interrupts at the same time a character is presented to the printer. 2. New Features None 3. Software Notes and Recommendations This patch should be installed on all UnixWare 1.1.1 systems which have high speed printers attached to them. This patch requires UnixWare 1.1.1 (UnixWare 1.1.1 is 1.1 with Update 5 installed) to be installed on the system. This patch is intended for UnixWare 1.1.1 systems only and cannot be installed on other systems. 4. Hardware Notes and Recommendations If slow printing occurs for any printer attached to the parallel port (as opposed to occurring for high speed printers only), the problem is more likely with the parallel port itself or possibly the cable by which the printer is attached. Some operating systems make no use of the acknowledge signal and cables intended for those environments sometimes are not wired to carry the signal. Our own investigation of this problem in our test center was delayed for several days due to a defective parallel port. 5. Installation Instructions Depending on the format: If this PTF was delivered on a diskette, then (as "root") pkgadd -d diskette1 should install this patch. Otherwise, if you have a file such as "ptf151" which is in a "stream" format, then (as "root") pkgadd -d /ptf151 will work. After installing this patch, a system reboot will be needed to rebuild the kernel and incorporate the updated driver. 6. Troubleshooting If you have a high speed printer that prints very slowly, you should observe a substantial improvement after installing this patch. If the printer still prints slowly, try a slower printer (such as a dot-matrix printer), if possible. If it also prints slowly, the problem is probably as described under "Hardware Notes and Recommendations" above.