公开(公告)号：DE69126187D1

公开(公告)日：1997-06-26

申请号：DE69126187

申请日：1991-10-30

Applicant: IBM

Inventor： LISLE RONALD J ,  MCDONALD BRADLEY SCOTT

IPC: G10H1/00 ,  G10H1/053 ,  G10H1/12

Abstract: A digital filter controlled by a plurality of filter coefficients is preferably coupled to the output of an excitation signal source within a MIDI synthesizer. The excitation signal source is typically controlled by a MIDI data file comprising a sequential series of program control commands and matching note on and note off commands. A plurality of filter coefficient factors are stored in memory and periodically accessed in response to variations in the program control commands and matching note on and note off commands. The selected filter coefficient factors are then utilised to calculate appropriate filter coefficients so that the centre frequency and filter Q of the digital filter may be dynamically and optimally controlled. In a preferred embodiment of the present invention a filter control circuit is also utilised to limit the output of the filter to a maximum level so that output stability is always maintained, independent of the initial conditions and filter coefficients of the filter.

公开(公告)号：BR8604619A

公开(公告)日：1987-05-26

申请号：BR8604619

申请日：1986-09-25

Applicant: IBM

Inventor： EINKAUF MARK ALAN ,  PARKER PAUL EDWARD ,  WEST LYNN PARKER ,  WILSON JOHN HAYDEN ,  HOEGH BRENT THOMAS ,  MCDONALD BRADLEY SCOTT

IPC: H04L29/10 ,  G06F13/00 ,  G06F13/38 ,  H04M11/00 ,  H04M11/06 ,  H04Q11/04

Abstract: A communication interface for providing asynchronous and telephonic communications is disclosed. The interface enables software applications, which are independent of any hardware or physical addresses, to operate on the interface. In this manner, the software applications can be written independent of hardware implementation and protocol implementation. A set of configuration parameters is defined for both an asynchronous and telephonic communication function set. Additionally, a set of interrupt conditions is defined for both the asynchronous and telephonic communication function sets. These parameters and interrupt conditions control the interaction of the software applications across the interface with the system hardware. Means are provided for directing commands coming from a software application across the interface to the system hardware. Likewise, means are provided for generating interrupts and handling these interrupts from the system hardware across the interface back to an interrupt routine within the software application.

公开(公告)号：DE69015714T2

公开(公告)日：1995-06-29

申请号：DE69015714

申请日：1990-06-07

Applicant: IBM

Inventor： KOVACH ROBERT CHARLES ,  MCDONALD BRADLEY SCOTT

IPC: G01R31/00 ,  G01R31/02 ,  G06F11/22 ,  G01R31/04

Abstract: A wrap test system automatically providing wrap interconnections for wrap diagnostic capability of electronic devices obviating the need for wrap cables. A connector system has a first state wherein DAC outputs are automatically internally routed to corresponding ADC inputs thereby closing a wrap loop whereupon automated DAC to ADC loop tests are performed. A second switching state is provided automatically by insertion of connector plugs into the connector system whereby the loop is broken and DAC outputs and ADC inputs are made available externally to respective output and input connectors.

公开(公告)号：DE69015714D1

公开(公告)日：1995-02-16

申请号：DE69015714

申请日：1990-06-07

Applicant: IBM

Inventor： KOVACH ROBERT CHARLES ,  MCDONALD BRADLEY SCOTT

IPC: G01R31/00 ,  G01R31/02 ,  G06F11/22 ,  G01R31/04

Abstract: A wrap test system automatically providing wrap interconnections for wrap diagnostic capability of electronic devices obviating the need for wrap cables. A connector system has a first state wherein DAC outputs are automatically internally routed to corresponding ADC inputs thereby closing a wrap loop whereupon automated DAC to ADC loop tests are performed. A second switching state is provided automatically by insertion of connector plugs into the connector system whereby the loop is broken and DAC outputs and ADC inputs are made available externally to respective output and input connectors.

公开(公告)号：BR9002866A

公开(公告)日：1991-08-20

申请号：BR9002866

申请日：1990-06-18

Applicant: IBM

Inventor： KOVACH ROBERT CHARLES ,  MCDONALD BRADLEY SCOTT

IPC: G01R31/00 ,  G01R31/02 ,  G06F11/22 ,  G06F11/00

Abstract: A wrap test system automatically providing wrap interconnections for wrap diagnostic capability of electronic devices obviating the need for wrap cables. A connector system has a first state wherein DAC outputs are automatically internally routed to corresponding ADC inputs thereby closing a wrap loop whereupon automated DAC to ADC loop tests are performed. A second switching state is provided automatically by insertion of connector plugs into the connector system whereby the loop is broken and DAC outputs and ADC inputs are made available externally to respective output and input connectors.