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Diagnostic Facility for a Print Control System

IP.com Disclosure Number: IPCOM000042570D
Original Publication Date: 1984-May-01
Included in the Prior Art Database: 2005-Feb-04
Document File: 2 page(s) / 53K

Publishing Venue

IBM

Related People

Bloom, RD: AUTHOR [+3]

Abstract

A diagnostic scan facility provides means for recording the status of eight or sixteen signals at selected recording rates. The scan facility has means for recording the status of any one signal at a different rate. The choice of signals, recording rate and length of recording time is controlled by a microprogram. As seen in the drawing, register A receives 8-bit scan control words on bus 10 from a microprocessor (MP). Decode 11 decodes bits 0-3 of the control words to provide byte selection signals for gating byte status signals on buses 12 through byte select gates 13 onto output bus 14 to register B. Decode 15, when enabled by the "ON" bit 4 of the control word in register A, decodes bits 5-7 to provide a bit selection signal for gating a single status bit of a status byte on output bus 14 into register B.

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Diagnostic Facility for a Print Control System

A diagnostic scan facility provides means for recording the status of eight or sixteen signals at selected recording rates. The scan facility has means for recording the status of any one signal at a different rate. The choice of signals, recording rate and length of recording time is controlled by a microprogram. As seen in the drawing, register A receives 8-bit scan control words on bus 10 from a microprocessor (MP). Decode 11 decodes bits 0-3 of the control words to provide byte selection signals for gating byte status signals on buses 12 through byte select gates 13 onto output bus 14 to register B. Decode 15, when enabled by the "ON" bit 4 of the control word in register A, decodes bits 5-7 to provide a bit selection signal for gating a single status bit of a status byte on output bus 14 into register B. Decode 17 when enabled by the "OFF" bit 4 of the control word decodes bits 6 and 7 of the control word in register A and supplies a rate select signal to rate select gates 18 which gates selected clocks to AND circuit 19 for setting rate valid latch 20. Rate select gates 18 gate a single bit rate to AND circuit 19 when bit 4 of the control word is "ON". The operation is as follows: In the eight-bit scan mode, register A bit 4 is "OFF" and selected status data gated by decode 11 through byte select gates onto bus 14 is clocked in register B at C1 time. At C2 time, status data in register B is transferred to regis...