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Re: ECB-DMA [message #8843 is a reply to message #8825]

Tue, 13 July 2021 11:44

lynchaj
Messages: 1080
Registered: June 2016

Senior Member

Hi
I've stared at these circuit and they seem equivalent to me. The top U1A AND gate is essentially just an input buffer which is the same function as the 74ls244. the U1B AND gate is literally unchanged. Possibly the 74ls244 input has schmitt trigger inputs and the 74ls08 does not? I think if any difference the right hand circuit would perform better with a signal from the bus than the left hand circuit.

If they are not equivalent then they're pretty close, AFAIK. I'd like to see some of the other people's thoughts & opinions on the subject. I learn something most every time.

Thanks, Andrew Lynch

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[Message index]

		ECB-DMA By: b1ackmai1er on Sun, 10 November 2019 00:16
		Re: ECB-DMA By: Wayne W on Tue, 12 November 2019 12:31
		Re: ECB-DMA By: jcoffman on Tue, 12 November 2019 16:14
		Re: ECB-DMA By: etchedpixels on Wed, 13 November 2019 15:40
		Re: ECB-DMA By: b1ackmai1er on Fri, 15 November 2019 20:34
		Re: ECB-DMA By: b1ackmai1er on Sat, 16 November 2019 04:56
		Re: ECB-DMA By: etchedpixels on Sat, 16 November 2019 05:23
		Re: ECB-DMA By: jcoffman on Sat, 16 November 2019 08:03
		Re: ECB-DMA By: wsm on Sat, 16 November 2019 09:28
		Re: ECB-DMA By: jcoffman on Sat, 16 November 2019 13:09
		Re: ECB-DMA By: wsm on Sat, 16 November 2019 14:02
		Re: ECB-DMA By: b1ackmai1er on Sun, 17 November 2019 05:50
		Re: ECB-DMA By: jcoffman on Sun, 17 November 2019 07:06
		Re: ECB-DMA By: etchedpixels on Sun, 17 November 2019 07:41
		Re: ECB-DMA By: wsm on Sun, 17 November 2019 10:06
		Re: ECB-DMA By: wsm on Sun, 17 November 2019 14:12
		Re: ECB-DMA By: jcoffman on Sun, 17 November 2019 21:28
		Re: ECB-DMA By: rcini on Thu, 12 December 2019 17:52
		Re: ECB-DMA By: wsm on Thu, 12 December 2019 21:24
		Re: ECB-DMA By: rcini on Fri, 13 December 2019 07:22
		Re: ECB-DMA By: mikesmith on Thu, 09 January 2020 18:36
		Re: ECB-DMA By: wsm on Thu, 09 January 2020 20:28
		Re: ECB-DMA By: lynchaj on Mon, 26 April 2021 09:03
		Re: ECB-DMA By: lynchaj on Tue, 27 April 2021 04:41
		Re: ECB-DMA By: lynchaj on Wed, 28 April 2021 08:00
		Re: ECB-DMA By: jcoffman on Sat, 16 November 2019 07:56
		Re: ECB-DMA By: jcoffman on Sat, 16 November 2019 07:45
		Re: ECB-DMA By: b1ackmai1er on Thu, 17 June 2021 07:14
		Re: ECB-DMA By: lynchaj on Thu, 17 June 2021 07:29
		Re: ECB-DMA By: b1ackmai1er on Sat, 19 June 2021 05:33
		Re: ECB-DMA By: lynchaj on Sat, 19 June 2021 07:11
		Re: ECB-DMA By: lynchaj on Sat, 19 June 2021 07:30
		Re: ECB-DMA By: b1ackmai1er on Mon, 21 June 2021 07:31
		Re: ECB-DMA By: b1ackmai1er on Sat, 26 June 2021 19:10
		Re: ECB-DMA By: b1ackmai1er on Fri, 02 July 2021 02:06
		Re: ECB-DMA By: lynchaj on Fri, 02 July 2021 04:49
		Re: ECB-DMA By: b1ackmai1er on Fri, 02 July 2021 07:23
		Re: ECB-DMA By: etchedpixels on Thu, 08 July 2021 08:22
		Re: ECB-DMA By: b1ackmai1er on Fri, 09 July 2021 22:08
		Re: ECB-DMA By: lynchaj on Tue, 13 July 2021 11:44
		Re: ECB-DMA By: lynchaj on Thu, 29 July 2021 12:15
		Re: ECB-DMA By: b1ackmai1er on Sun, 04 July 2021 08:09
		Re: ECB-DMA By: b1ackmai1er on Mon, 05 July 2021 07:35
		Re: ECB-DMA By: lynchaj on Wed, 07 July 2021 03:27
		Re: ECB-DMA By: lynchaj on Wed, 07 July 2021 03:44
		Re: ECB-DMA By: lynchaj on Mon, 14 March 2022 03:48
		Re: ECB-DMA By: lynchaj on Wed, 23 March 2022 10:05

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