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Question ISA BUS clock [message #6191]

Fri, 29 March 2019 00:20

32768
Messages: 4
Registered: October 2018

Junior Member

From this picture https://upload.wikimedia.org/wikipedia/commons/9/9f/ISA_Bus_ pins.svg Which one is the ISA bus clock? B20 or B30?

Also from http://www.hardwarebook.info/ISA it shows ALE high at the clock cycle low, but from my measurements, my ALE behave very differently from what they show in the 8 Bit Memory or I/O Transfer Timing Diagram (4 wait states shown). So before I do something irreversible... I had to ask.

[Updated on: Fri, 29 March 2019 00:21]

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[Message index]

		Question ISA BUS clock By: 32768 on Fri, 29 March 2019 00:20
		Re: Question ISA BUS clock By: monahan on Sat, 30 March 2019 08:15
		Re: Question ISA BUS clock By: 32768 on Sun, 31 March 2019 08:46
		Re: Question ISA BUS clock By: Andrew B on Sun, 31 March 2019 12:51
		Re: Question ISA BUS clock By: Sergey on Mon, 01 April 2019 12:01
		Re: Question ISA BUS clock By: 32768 on Tue, 02 April 2019 00:07
		Re: Question ISA BUS clock By: Sergey on Tue, 02 April 2019 01:31
		Re: Question ISA BUS clock By: 32768 on Sun, 07 April 2019 22:48
		Re: Question ISA BUS clock By: Sergey on Mon, 08 April 2019 16:33

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