Circuitry for Transforming 'STROBE' Edges into 'STROBE' Pulses
Original Publication Date: 1993-Jul-01
Included in the Prior Art Database: 2005-Mar-19
Publishing Venue
IBM
Related People
Hennet, PP: AUTHOR [+3]
Abstract
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Circuitry for Transforming 'STROBE' Edges into 'STROBE' Pulses
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Data Bit 0 | |
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Data Bit 1 | | |
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---- ----- -----
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-Strobe | |
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----- -----
----- ----- -
---- --------- ---------
Edge Mode Strobe | |
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Figure 1 - Possible Input Strobe Signals
Disclosed is
circuitry to allow a sequential memory measurement
instrument to convert 'STROBE' edges into 'STROBE' pulses of the
proper phase. This circuitry will also
double the frequency of the
input signal.
A sequential
memory system is built to accept data from a
remote hardware system. The remote
hardware system must send n bits
of data to be stored and a 'STROBE' signal that signifies when the n
bits of data are valid. Fig. 1 shows
what two of the possible n data
bits could look like. The '-Strobe'
signal in Fig. 1 is an example
of the proper negative going 'STROBE' signal.
This '-Strobe' signal
must have a negative going edge every time the data bits can change
to a new value. The interface could not
provide the '-Strobe'
signal. The signal that could be
provided was the signal called
'Edge Mode Strobe' in Fig. 1. This
signal changes edges everytime
the data is valid. The problem is to
provide circuitry that will
transform the 'Edge Mode Strobe' into the same form as the '-Strobe'
signal. This requires that each edge of
the 'Edge Mode Strobe' be
converted into a negative going pulse.
It is also desired that the
circuit also accept the '-Strobe' signal and work correctly.
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Edge Mode Strobe -------------------------> XOR | -Strobe
| ...