4 ms·

A funny quote if you put on your layman's glasses: > It's simply a 24C02 EEPROM with 4.7K pull-ups on I2C lines, a bypass cap, and some diodes, probably for re

by dgb23 4y ago

A funny quote if you put on your layman's glasses: > It's simply a 24C02 EEPROM with 4.7K pull-ups on I2C lines, a bypass cap, and some diodes, probably for reverse-insertion protection.

mgdlbp 4y ago
Hence the Rewinder as a product: just plug it into the cassette and reprogram at the press of a button.
tinco 4y ago
It is very heavy on the jargon indeed. Just in case someone's wondering, the author isn't being facetious it really is a very simple thing. If you google 24C02 you'll get a PDF that probably has this exact schematic in the application examples section. If you want to take up electronics design as a hobby, you'd probably be at the level where you could have this designed and manufactured within a month or two of evening/weekends studies. edit: Just for fun, let's go through the jargon. 24C02 EEPROM is the name of a popular chip that stores a tiny bit of persistent memory. Mouser at the moment has more than 80 variations of this chip with hundreds of thousands in stock and hundreds of thousands more in back order. 4.7k pull-ups, this means there's a small resistor between the signal lines and the positive voltage rail. This enables the chip to communicate by pulling the signal low (by shorting it to ground) this way of signalling is very common, someone told me it's because how the telegraph worked but I'm not sure if that's true. I2C is a simple communication protocol that works if chips are really close together (i.e. I think guideline is within 10-15cm). A bypass capacitor is a component that blocks continuous voltage but lets oscillating voltage through. Most chips don't deal well with oscillating voltages on their power supplies so the manufacturer will recommend you (through that PDF I mentioned before) to put a bypass capacitor between the power supply line and the ground, so that the dirty oscillations go directly to ground instead of into your chip. A diode is a component where current can only go in one direction, in this case that's handy because chips usually break if you wire them in reverse polarity. If a user would force this cartridge in backwards, instead of the chip blowing up, the diodes will simply block the current from coming in the wrong way and the device won't work. And that's it, I think all you need to understand how this cartridge is designed.
dj_mc_merlin 4y ago
We do the same, right? Oh, it's simply routed to by a reverse-proxy nginx behind a round-robin load balancer with a long deregistration delay, probably to let the application shut down gracefully. If I try to forget for a second.. what the fuck did I just say?
Graziano_M 4y ago
In layman's terms: It's an integrated circuit that has non-volatile storage, resistors on the data lines so that the voltage sits at 'high', as per the spec for I2C (the communication protocol), a capacitor to stabilize the voltage, and diodes that protect the circuit in case voltage were applied in the 'wrong direction'.

by dgb23 4y ago

A funny quote if you put on your layman's glasses: > It's simply a 24C02 EEPROM with 4.7K pull-ups on I2C lines, a bypass cap, and some diodes, probably for reverse-insertion protection.

mgdlbp 4y ago

Hence the Rewinder as a product: just plug it into the cassette and reprogram at the press of a button.

tinco 4y ago

It is very heavy on the jargon indeed. Just in case someone's wondering, the author isn't being facetious it really is a very simple thing. If you google 24C02 you'll get a PDF that probably has this exact schematic in the application examples section. If you want to take up electronics design as a hobby, you'd probably be at the level where you could have this designed and manufactured within a month or two of evening/weekends studies. edit: Just for fun, let's go through the jargon. 24C02 EEPROM is the name of a popular chip that stores a tiny bit of persistent memory. Mouser at the moment has more than 80 variations of this chip with hundreds of thousands in stock and hundreds of thousands more in back order. 4.7k pull-ups, this means there's a small resistor between the signal lines and the positive voltage rail. This enables the chip to communicate by pulling the signal low (by shorting it to ground) this way of signalling is very common, someone told me it's because how the telegraph worked but I'm not sure if that's true. I2C is a simple communication protocol that works if chips are really close together (i.e. I think guideline is within 10-15cm). A bypass capacitor is a component that blocks continuous voltage but lets oscillating voltage through. Most chips don't deal well with oscillating voltages on their power supplies so the manufacturer will recommend you (through that PDF I mentioned before) to put a bypass capacitor between the power supply line and the ground, so that the dirty oscillations go directly to ground instead of into your chip. A diode is a component where current can only go in one direction, in this case that's handy because chips usually break if you wire them in reverse polarity. If a user would force this cartridge in backwards, instead of the chip blowing up, the diodes will simply block the current from coming in the wrong way and the device won't work. And that's it, I think all you need to understand how this cartridge is designed.

dj_mc_merlin 4y ago

We do the same, right? Oh, it's simply routed to by a reverse-proxy nginx behind a round-robin load balancer with a long deregistration delay, probably to let the application shut down gracefully. If I try to forget for a second.. what the fuck did I just say?

Graziano_M 4y ago

In layman's terms: It's an integrated circuit that has non-volatile storage, resistors on the data lines so that the voltage sits at 'high', as per the spec for I2C (the communication protocol), a capacitor to stabilize the voltage, and diodes that protect the circuit in case voltage were applied in the 'wrong direction'.