Apple 1 - My Terminal Circuit Works, Next Microprocessor Circuit

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Apple 1 - My Terminal Circuit Works, Next Microprocessor Circuit

Success - my Apple 1 Terminal Circuit is working.

Changed the 74LS161AN in D8 to 74161, and both C4 and C14 74LS157 to 74157.

Many thanks for the many people who have helped me get to this point.Looking at Post #21 of french-ie-newb-ie-apple-one-ie I'm only half way as the Microprocessor part is not working.

I fould an "old school" electronics store in Melbourne, so on Monday I will see which other ICs they have.

My mainboard is fully populated.

I connected a multimeter between GND and 6502 Pin40 and pressing RESET voltage goes from 5.01V to 0.02V.

 

 

 

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Infrared Camera at Steady State

Temperatures of Hotter Components:

D8, 74161 = 48C (118F) compared to [92F]D1, 74LS166 = 61C (142F) compared to [91F]

C14, 74157 = 44C (111F) 

C3, 7=2519N = 53C(127F) compared to [94F]

A10, 8T97 = 45C (113F) compared to [85F]

A9, 8T97=  48C (118F) compared to [85F]

A6-8, 6502 = 53C (127F) compared to [88F]

A2 PROM = 49C (120F) compared to [79F]

A1, PROM = 51C (124F) compared to [79F]

 

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Heat Sink Temperature

LM323 Centre = 43C (109F)  - [177F]Heat Sink = 64C (147F) 

7905 = 47C (117F) compared to [133F]

7912 (+Heatsink) = 46C (115F) copared to [123F]

7812 = 52C (126F) compared to [110F]Comparision: french-ie-newb-ie-apple-one-ie Post #33 - [Square Parentheses], this was after 10 minutes.

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Well done !

The display part works and that's a good thing!

You saw my thread, so you can check the jumpers including DMA and 6502 .

I can't see them clearly in the previous picture .

Can you post a photo of the motherboard in high resolution?

Did you put the 2nd row of ram?

For troubleshooting, Uncle Bernie's binary split method is a great help :

https://www.applefritter.com/content/what-do-deafdumbdead-apple-1-cpu-section

 

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Thank you, once I changed the

Thank you, once I changed the 74LS161AN in D8 to 74161, the terminal section worked as intended.  Also replaced C4 and C14 from 74LS157 to 74157

I ahve the following Jumpers, Both 6502, DMA, Y-F, Z-C, X-0, I have not installed the ACI yet so connection C-R is still open.More good news, I have the Microprocessor section working, but see I still have a samll problem with the terminal.

After a Full Reset and typing myname I see this, with both Ampersand flashing:

I can run the 0:A9 00 AA 20 EF ff E8 8A 4C 2 0 program, the output comes on 3 to 4 lines as the cursor does not know where it is.

I've found a local supplier of the orginal logic ICs so will try replacing a few more tomorrow, will doubl check C5, 7427

If  I type continuous "with no pauses" occasionally the character skips to the line below, then if I carry on ttping it stats on the top line.

I'm check the main board for faults as my soldering skills are now "not great", but Ok.

Pressing Carriage Return does not advance a line on the screen, will check C4, C5, C6, C7, C8 and C9 again. 

Will also take a look at the cursor control C11B and C13.

 

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More Progress

Replaced the 74Ls32 at C9 with a 7432.  Live form Australia.I may take a few days rest now.  Then add second row of memory and see how stable the system is.  Then I need to finish the GEN 2 ACI by Uncle Bernie.  I have everything complete, except the Surface Mount Components.Thank you to all who are helping me, your knowledge and support has kept me goin. 

Best Freinds :-)

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Hi RussellSpeight1967!

If you use the right chips everything is much simpler, isn't it? ) :

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Congratulations

 

 

For the ACI GEN 2 only soldering the three-pin SMD component  is tricky.

I suggest soldering first so as not to be bothered by the other SMDs...

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Awesome!

Awesome!

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Thank you all for support.I

Thank you all for support.I used a 'Surface Mount Practice Kit' which really helped.

ACI is all together, LED works.

Using an iPhone with Stereo plug to Mono plug, as suggested, no 1.2K Ohm resistor.

Signal to socket looks like this [~2Volt Peak to Peak].
and the output from pin 7 of the LM311P Comparator looks like [5Volt peak to peak]:"These are for different time slices, so should not be in sync".

I've looked through WOZACI assembler code, to understand what I should be see'ing.

Memory E000-EFFF is writeable, I wrote a simple routine to check."First Attempt":C100R [CR]gives:C100: A9*

E000.EFFFRThen start the BASIC audio file [38 seconds length].Press [CR]Next character that pops up is a flashing "@" or solid "*".

That's as far I as I managed today :-)

 

 

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Its working :-)

Its working :-)

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Hi RussellSpeight1967!

Hi! Good for you that everything worked out and welcome to the wonderful world of Apple-1. If you want you can try to download other programs and games via your ACI card. I've collected some programs, I'll be glad if you like them.

https://disk.yandex.ru/d/PkeDgYyDib1gqw

 

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Ran the Apple-1 overnight

Ran the Apple-1 overnight running simple BASIC program, no fuses blew, no fires :-)

Will push all the ICs back into their sockets and try loading something other than BASIC.

I like having the scope connected to the audio input, so know when to hit Return.

This weekend I will try writing to audio file.

Need a retro looking casette recorder, that is digital inside.

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Return

you can type return first and then launch play without any problem with a phone

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Gen2 ACI is working very well

Gen2 ACI is working very well.

Loading and saving data, very reliabily.

Now to start and do some programming.

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