Talk:Latch - Revision history

Jnc: /* Latches/Flops */ More changing types

2018-03-15T09:00:27Z

‎Latches/Flops: More changing types

Jnc: Alas, I may have just broken it! :-)

2018-03-15T08:52:53Z

Alas, I may have just broken it! :-)

Tor: Looks fine

2018-03-15T08:25:01Z

Looks fine

Jnc: Yes, still lots of confusion

2018-03-13T17:11:09Z

Yes, still lots of confusion

Larsbrinkhoff: It's the same to some people!

2018-03-13T13:26:24Z

It's the same to some people!

Jnc: /* Latches/Flops */ Hmmmm

2018-03-13T13:16:44Z

‎Latches/Flops: Hmmmm

Larsbrinkhoff: Inappropriate redirect?

2018-03-12T08:43:18Z

Inappropriate redirect?

Tor: flip-flops != latches (not all the time at least)

2018-03-12T08:36:29Z

flip-flops != latches (not all the time at least)

Larsbrinkhoff: Not same.

2018-03-12T06:47:31Z

Not same.

New page

My digital design friends tell me there's a distinction between latches and flip-flops. [[User:Larsbrinkhoff|Larsbrinkhoff]] ([[User talk:Larsbrinkhoff|talk]])

@@ Line 22: / Line 22: @@
 : Looks pretty good now! [[User:Tor|Tor]] ([[User talk:Tor|talk]]) 09:24, 15 March 2018 (CET)
-:: Alas, in reading about various kinds of flip-flops in the TI TTL reference book, I discovered things are even more complex than I realized! See, e.g. the 7473 and 74LS73 - which have different clocking! So I've now added a section which attempts to give a general, systematic framework for understanding flops/latches: when they look at the inputs, etc.
+:: Alas, in reading about various kinds of flip-flops in the TI TTL reference book, I discovered things are even more complex than I realized! See, e.g. the 7473/6/8 and 74LS73/6/8 - which have different clocking! So I've now added a section which attempts to give a general, systematic framework for understanding flops/latches: when they look at the inputs, etc.
 :: I ''hope'' I've made things better; the text may be more complex now, but alas the reality is complex, and I ''think'' I have captured things in a way which makes the complexity easier to grasp. But I'd be interested in feedback! [[User:Jnc|Jnc]] ([[User talk:Jnc|talk]]) 09:52, 15 March 2018 (CET)

← Older revision		Revision as of 08:52, 15 March 2018
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	: Looks pretty good now! [[User:Tor\|Tor]] ([[User talk:Tor\|talk]]) 09:24, 15 March 2018 (CET)		: Looks pretty good now! [[User:Tor\|Tor]] ([[User talk:Tor\|talk]]) 09:24, 15 March 2018 (CET)
		+
		+	:: Alas, in reading about various kinds of flip-flops in the TI TTL reference book, I discovered things are even more complex than I realized! See, e.g. the 7473 and 74LS73 - which have different clocking! So I've now added a section which attempts to give a general, systematic framework for understanding flops/latches: when they look at the inputs, etc.
		+	:: I ''hope'' I've made things better; the text may be more complex now, but alas the reality is complex, and I ''think'' I have captured things in a way which makes the complexity easier to grasp. But I'd be interested in feedback! [[User:Jnc\|Jnc]] ([[User talk:Jnc\|talk]]) 09:52, 15 March 2018 (CET)

← Older revision		Revision as of 08:25, 15 March 2018
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	::: Yup. In fact, I just recently had confusion talking to my partner on the QSIC project about state storage devices - as part of clearing it up, he introduced me to the 'transparent' terminology.		::: Yup. In fact, I just recently had confusion talking to my partner on the QSIC project about state storage devices - as part of clearing it up, he introduced me to the 'transparent' terminology.
	::: But I had a bit of hard time compressing it all into short text. The issue was S-R device, which doesn't have a 'data' input, ''or'' a clock, and is not (strictly speaking) 'transparent'! It's too primitive! And the J-K flop, which doesn't have a data input, didn't help! Eventually I resorted to saying 'flops are now so-and-so, everything else is latches'! [[User:Jnc\|Jnc]] ([[User talk:Jnc\|talk]]) 18:10, 13 March 2018 (CET)		::: But I had a bit of hard time compressing it all into short text. The issue was S-R device, which doesn't have a 'data' input, ''or'' a clock, and is not (strictly speaking) 'transparent'! It's too primitive! And the J-K flop, which doesn't have a data input, didn't help! Eventually I resorted to saying 'flops are now so-and-so, everything else is latches'! [[User:Jnc\|Jnc]] ([[User talk:Jnc\|talk]]) 18:10, 13 March 2018 (CET)
		+
		+	: Looks pretty good now! [[User:Tor\|Tor]] ([[User talk:Tor\|talk]]) 09:24, 15 March 2018 (CET)

@@ Line 11: / Line 11: @@
 :* Separate articles would therefore have a lot of duplication
 :* Historically (and this is a ''history'' wiki :-), the terms were not so carefully delineated; e.g. in Pfister's book (he's the guy who came up with the whole SR/D/JK/T nomenclature), he talks about "R-S flip-flops"
 :: I talked to another friend, and he was vehement that they were the same thing.  So clearly it's unclear. :-) [[User:Larsbrinkhoff|Larsbrinkhoff]] ([[User talk:Larsbrinkhoff|talk]])
-I will definitely try and make clearer (than it already is) that in ''contemporary'' terminology, the two terms refer to disjoint sets. See what you think... [[User:Jnc|Jnc]] ([[User talk:Jnc|talk]]) 14:15, 13 March 2018 (CET)

@@ Line 11: / Line 11: @@
 :* Separate articles would therefore have a lot of duplication
 :* Historically (and this is a ''history'' wiki :-), the terms were not so carefully delineated; e.g. in Pfister's book (he's the guy who came up with the whole SR/D/JK/T nomenclature), he talks about "R-S flip-flops"
 I will definitely try and make clearer (than it already is) that in ''contemporary'' terminology, the two terms refer to disjoint sets. See what you think... [[User:Jnc|Jnc]] ([[User talk:Jnc|talk]]) 14:15, 13 March 2018 (CET)

@@ Line 1: / Line 1: @@
 My digital design friends tell me there's a distinction between latches and flip-flops. [[User:Larsbrinkhoff|Larsbrinkhoff]] ([[User talk:Larsbrinkhoff|talk]])
 :Your friends are right. Wikipedia uses the confusing 'a flip-flop or latch is..', which is easy to interpret to mean that 'latch' is just another word for 'flip-flop', which is not what is meant. There is a distinction, although there's overlap (b/c there are different types of latches). And when I design something I think of latches and flip-flops as entirely different things (e.g. flip-flops to divide or fix clock signals, latches to buffer/hold data). (Here's a web page which talks about flip-flops vs latches): http://www.electronicsteacher.com/computer-architectures/digital-circuits/flip-flops.php [[User:Tor|Tor]] ([[User talk:Tor|talk]]) 09:35, 12 March 2018 (CET)
 :: Thanks.  Then maybe the redirect from Latch to Flip-flop isn't entirely appropriate.  Although, it might be better than nothing. [[User:Larsbrinkhoff|Larsbrinkhoff]] ([[User talk:Larsbrinkhoff|talk]])

← Older revision		Revision as of 08:43, 12 March 2018
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	My digital design friends tell me there's a distinction between latches and flip-flops. [[User:Larsbrinkhoff\|Larsbrinkhoff]] ([[User talk:Larsbrinkhoff\|talk]])		My digital design friends tell me there's a distinction between latches and flip-flops. [[User:Larsbrinkhoff\|Larsbrinkhoff]] ([[User talk:Larsbrinkhoff\|talk]])
	:Your friends are right. Wikipedia uses the confusing 'a flip-flop or latch is..', which is easy to interpret to mean that 'latch' is just another word for 'flip-flop', which is not what is meant. There is a distinction, although there's overlap (b/c there are different types of latches). And when I design something I think of latches and flip-flops as entirely different things (e.g. flip-flops to divide or fix clock signals, latches to buffer/hold data). (Here's a web page which talks about flip-flops vs latches): http://www.electronicsteacher.com/computer-architectures/digital-circuits/flip-flops.php [[User:Tor\|Tor]] ([[User talk:Tor\|talk]]) 09:35, 12 March 2018 (CET)		:Your friends are right. Wikipedia uses the confusing 'a flip-flop or latch is..', which is easy to interpret to mean that 'latch' is just another word for 'flip-flop', which is not what is meant. There is a distinction, although there's overlap (b/c there are different types of latches). And when I design something I think of latches and flip-flops as entirely different things (e.g. flip-flops to divide or fix clock signals, latches to buffer/hold data). (Here's a web page which talks about flip-flops vs latches): http://www.electronicsteacher.com/computer-architectures/digital-circuits/flip-flops.php [[User:Tor\|Tor]] ([[User talk:Tor\|talk]]) 09:35, 12 March 2018 (CET)
		+	:: Thanks. Then maybe the redirect from Latch to Flip-flop isn't entirely appropriate. Although, it might be better than nothing. [[User:Larsbrinkhoff\|Larsbrinkhoff]] ([[User talk:Larsbrinkhoff\|talk]])

← Older revision		Revision as of 08:36, 12 March 2018
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	My digital design friends tell me there's a distinction between latches and flip-flops. [[User:Larsbrinkhoff\|Larsbrinkhoff]] ([[User talk:Larsbrinkhoff\|talk]])		My digital design friends tell me there's a distinction between latches and flip-flops. [[User:Larsbrinkhoff\|Larsbrinkhoff]] ([[User talk:Larsbrinkhoff\|talk]])
		+	:Your friends are right. Wikipedia uses the confusing 'a flip-flop or latch is..', which is easy to interpret to mean that 'latch' is just another word for 'flip-flop', which is not what is meant. There is a distinction, although there's overlap (b/c there are different types of latches). And when I design something I think of latches and flip-flops as entirely different things (e.g. flip-flops to divide or fix clock signals, latches to buffer/hold data). (Here's a web page which talks about flip-flops vs latches): http://www.electronicsteacher.com/computer-architectures/digital-circuits/flip-flops.php [[User:Tor\|Tor]] ([[User talk:Tor\|talk]]) 09:35, 12 March 2018 (CET)