Hi Guys
I’m making an eight bit wide core rope memory.
Roughly following Kos’ previous example doesn’t take one as far as reading the memory
into digital inputs, so from here I'll have to wing it, and experiment with external circuitry.
For this reason, I’ve made a single ferrite version of the circuit for proving examples with first.
I’ve also recorded this single ferrite circuit:
http://img.photobucket.com/albums/v186/ArtArt/Test_Circuit_Schema_zpsqs4mhycd.png
From here I will be wanting to increment each wire with a decade counter or shift register,
to detect pulses at the transformer secondaries with an eight bit parallel port.
So other than testing the memory weaving, I’ll not actually be needing the 555 oscillator.
555 oscillator PCB:
http://img.photobucket.com/albums/v186/ArtArt/555_oscillator_zpsgyhpr3qj.png
Ferrite PCB:
http://img.photobucket.com/albums/v186/ArtArt/One_Bit_LED_zpscfgfyabt.png
I have so far reproduced Kos’ experiment... (virtually).. I didn’t bother to wire seven set LED patterns.
http://qrp.gr/coreROM/
Here is a video including the eight bit board with two full bytes test ROM:
Questions
1) Are there any considerations to make for the input to a micro or parallel to serial shift register
from the transformer secondaries? Diode clamping is one I can think of perhaps.
2) Do I need a current limiting resistor on each of the supply pins from a logic chip to a primary wire?
I notice in the circuit above, that if I disconnect the DC driven output LED (on the 555 circuit),
the 555 output has more current to drive the AC coupled LEDs brighter.
This is more noticeable on the eight bit board where 8 LEDs can be driven together,
and they are not high intensity LEDs.
3) Do you have any other suggestions? My next step is to automate the input signals,
and try reading the output pulses digitally with a micro, either directly, or indirectly.
Cheers, Art.
I’m making an eight bit wide core rope memory.
Roughly following Kos’ previous example doesn’t take one as far as reading the memory
into digital inputs, so from here I'll have to wing it, and experiment with external circuitry.
For this reason, I’ve made a single ferrite version of the circuit for proving examples with first.
I’ve also recorded this single ferrite circuit:
http://img.photobucket.com/albums/v186/ArtArt/Test_Circuit_Schema_zpsqs4mhycd.png
From here I will be wanting to increment each wire with a decade counter or shift register,
to detect pulses at the transformer secondaries with an eight bit parallel port.
So other than testing the memory weaving, I’ll not actually be needing the 555 oscillator.
555 oscillator PCB:
http://img.photobucket.com/albums/v186/ArtArt/555_oscillator_zpsgyhpr3qj.png
Ferrite PCB:
http://img.photobucket.com/albums/v186/ArtArt/One_Bit_LED_zpscfgfyabt.png
I have so far reproduced Kos’ experiment... (virtually).. I didn’t bother to wire seven set LED patterns.
http://qrp.gr/coreROM/
Here is a video including the eight bit board with two full bytes test ROM:
Questions
1) Are there any considerations to make for the input to a micro or parallel to serial shift register
from the transformer secondaries? Diode clamping is one I can think of perhaps.
2) Do I need a current limiting resistor on each of the supply pins from a logic chip to a primary wire?
I notice in the circuit above, that if I disconnect the DC driven output LED (on the 555 circuit),
the 555 output has more current to drive the AC coupled LEDs brighter.
This is more noticeable on the eight bit board where 8 LEDs can be driven together,
and they are not high intensity LEDs.
3) Do you have any other suggestions? My next step is to automate the input signals,
and try reading the output pulses digitally with a micro, either directly, or indirectly.
Cheers, Art.
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