IPDS error recovery
When driving an IPDS printer, InfoPrint Manager sends page and resource data to the printer. The printer reports status and errors back to InfoPrint Manager. The printer status information is in the form of station counters representing progress of pages sent to the device through the printer microcode and the physical printing mechanism. Station counters report the number of pages and the number of copies of pages proceeding through each point in the printer.
InfoPrint Manager requests printer status information (an acknowledgement request) after sending each job. The acknowledgement response contains the latest values of all the printer station counters. Once all pending jobs have been processed, InfoPrint Manager polls the printer periodically until all the pages of each job have been stacked.
The actual destination object ack-interval attribute is configurable and defines how often InfoPrint Manager requests updated station counters from the printer while processing a particular job. The value for this attribute is specified in terms of pages and can be from 1 to 9999; the default value is 100 pages. For a 360 page job, an ack-interval setting of 100 pages means that InfoPrint Manager will send an acknowledgement request to the printer after sending pages 100, 200, 300, and 360.
The printer responds to an acknowledgement request and returns station counters when all of the pages up to that point have been processed. This does not necessarily mean that all of those pages have printed or are stacked. The acknowledgement response from the printer after the 100th page will show that 100 pages have been processed (received). The printer might report, however, that only 10 pages have stacked.
The ack-interval value affects printing performance and the currency of job status information. A small ack-interval value causes increased communication and processing and can cause a reduction in printer throughput. A small ack-interval value will, however, increase the frequency that job attributes such as current-page-printing, job-copies-completed, media-sheets-completed, and pages-completed are updated. A small ack-interval value will also enable the InfoPrint Manager software to have more recent station counters than it would with a large ack-interval value.
Errors reported from the printer can be grouped into these categories: