DEC edge connector contact identification - Revision history

Jnc: slot-centric and board-centric naming

2020-05-16T16:20:46Z

slot-centric and board-centric naming

← Older revision		Revision as of 16:20, 16 May 2020
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	The edge connector contact groups of [[Digital Equipment Corporation\|DEC]] cards such as [[FLIP CHIP]]s on the edge of a [[DEC card form factor\|hex]] card are 'numbered' A-F. The groups are often called 'rows' in DEC documentation; the term 'slots' is also used, but this is confusing, because [[backplane]]s also have numbered slots for cards, numbered horizontally. The term 'connector' is also seen.		The edge connector contact groups of [[Digital Equipment Corporation\|DEC]] cards such as [[FLIP CHIP]]s on the edge of a [[DEC card form factor\|hex]] card are 'numbered' A-F (for smaller cards, see below). The groups are often called 'rows' in DEC documentation; the term 'slots' is also used, but this is confusing, because [[backplane]]s also have numbered slots for cards, numbered horizontally. The term 'connector' is also seen.

	The groups are 'numbered' starting from the top (when the card is installed, vertically), with 'A'; this would be the right-hand edge, when the card is horizontal, with the component side up, and the connector 'fingers' ''toward'' the viewer. Shorter cards (quads and duals) use subsets of these, also starting with 'A'.		The groups are 'numbered' starting from the top (when the card is installed, vertically), with 'A'; this would be the right-hand edge, when the card is horizontal, with the component side up, and the connector 'fingers' ''toward'' the viewer. Shorter cards (quads and duals) use subsets of these, also starting with 'A'.

	Within each row, the individual contacts are 'numbered' from the [[DEC Alphabet]]; those on the component side are further numbered '1', and those on the solder side (for boards with contacts on both sides - not all do), '2'. I.e. with the board in a horizontal position, as described above, the right-most contact on the top side (i.e. visible) would be identified as 'AA1'.		Within each row, the individual contacts are 'numbered' from the [[DEC Alphabet]]; those on the component side are further numbered '1', and those on the solder side (for boards with contacts on both sides - not all do), '2'. I.e. with the board in a horizontal position, as described above, the right-most contact on the top side (i.e. visible) would be identified as 'AA1'.

			For smaller cards (quads and duals), DEC used two contradictory systems: one, which we can call 'board-centric', identified the top connector (on boards of any size ) as 'A', and continued in alphabetic sequence from there; the other, which we can call 'slot-centric', identified the connectors by the slot connector into which it plugged. (The [[RK11 disk controller#RK11-D\|RK11-D]] engineering drawings actually have a page which shows both systems applied to one of the RK11-D's quad cards.)

			The apparent reason for the use of two contradictory (and thus potentially confusing) systems is that the slot-centric system works better for cards destined for a unique, fixed slot in a single type of backplane; the board-centric system is better for cards like early FLIP CHIPs, which were generic, and appeared in different locations on different backplanes.

	==See also==		==See also==

	* [[DEC card form ~~factor‎~~]]		* [[DEC card form factor]]

	[[Category: DEC Hardware]]		[[Category: DEC Hardware]]

Jnc: +cat

2018-12-16T04:08:14Z

+cat

← Older revision		Revision as of 04:08, 16 December 2018
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	* [[DEC card form factor‎]]		* [[DEC card form factor‎]]

			[[Category: DEC Hardware]]

Jnc: Names for connector groups

2018-01-03T22:23:40Z

Names for connector groups

← Older revision		Revision as of 22:23, 3 January 2018
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	The edge connector contact groups of [[Digital Equipment Corporation\|DEC]] cards such as [[FLIP CHIP]]s ~~(often called 'rows', in DEC documentation)~~ on the edge of a [[DEC card form factor\|hex]] card are 'numbered' A-F, starting from the top (when the card is installed, vertically); this would be the right-hand edge, when the card is horizontal, with the component side up, and the connector 'fingers' ''toward'' the viewer. Shorter cards (quads and duals) use subsets of these, starting with 'A'.		The edge connector contact groups of [[Digital Equipment Corporation\|DEC]] cards such as [[FLIP CHIP]]s on the edge of a [[DEC card form factor\|hex]] card are 'numbered' A-F. The groups are often called 'rows' in DEC documentation; the term 'slots' is also used, but this is confusing, because [[backplane]]s also have numbered slots for cards, numbered horizontally. The term 'connector' is also seen.

			The groups are 'numbered' starting from the top (when the card is installed, vertically), with 'A'; this would be the right-hand edge, when the card is horizontal, with the component side up, and the connector 'fingers' ''toward'' the viewer. Shorter cards (quads and duals) use subsets of these, also starting with 'A'.

	Within each row, the individual contacts are 'numbered' from the [[DEC Alphabet]]; those on the component side are further numbered '1', and those on the solder side (for boards with contacts on both sides - not all do), '2'. I.e. with the board in a horizontal position, as described above, the right-most contact on the top side (i.e. visible) would be identified as 'AA1'.		Within each row, the individual contacts are 'numbered' from the [[DEC Alphabet]]; those on the component side are further numbered '1', and those on the solder side (for boards with contacts on both sides - not all do), '2'. I.e. with the board in a horizontal position, as described above, the right-most contact on the top side (i.e. visible) would be identified as 'AA1'.

Jnc: Add see also

2017-12-17T00:02:52Z

Add see also

← Older revision		Revision as of 00:02, 17 December 2017
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	Within each row, the individual contacts are 'numbered' from the [[DEC Alphabet]]; those on the component side are further numbered '1', and those on the solder side (for boards with contacts on both sides - not all do), '2'. I.e. with the board in a horizontal position, as described above, the right-most contact on the top side (i.e. visible) would be identified as 'AA1'.		Within each row, the individual contacts are 'numbered' from the [[DEC Alphabet]]; those on the component side are further numbered '1', and those on the solder side (for boards with contacts on both sides - not all do), '2'. I.e. with the board in a horizontal position, as described above, the right-most contact on the top side (i.e. visible) would be identified as 'AA1'.

			==See also==

			* [[DEC card form factor‎]]

Jnc: Created page with "The edge connector contact groups of DEC cards such as FLIP CHIPs (often called 'rows', in DEC documentation) on the edge of a DEC card..."

2017-12-16T23:35:58Z

Created page with "The edge connector contact groups of DEC cards such as FLIP CHIPs (often called 'rows', in DEC documentation) on the edge of a DEC card..."

New page

The edge connector contact groups of [[Digital Equipment Corporation|DEC]] cards such as [[FLIP CHIP]]s (often called 'rows', in DEC documentation) on the edge of a [[DEC card form factor|hex]] card are 'numbered' A-F, starting from the top (when the card is installed, vertically); this would be the right-hand edge, when the card is horizontal, with the component side up, and the connector 'fingers' ''toward'' the viewer. Shorter cards (quads and duals) use subsets of these, starting with 'A'.

Within each row, the individual contacts are 'numbered' from the [[DEC Alphabet]]; those on the component side are further numbered '1', and those on the solder side (for boards with contacts on both sides - not all do), '2'. I.e. with the board in a horizontal position, as described above, the right-most contact on the top side (i.e. visible) would be identified as 'AA1'.