rackandboneman
  • Member for 5 years, 8 months
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Checklist for powering up an Apple IIgs?
8 votes

Generic answer, applies to any machine of a similar design in that condition: If you can, check the power supplies (not just for the machine preferably, on anything you are attempting to connect to ...

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PCB Black Spot: Leakage?
2 votes

That looks like long-term heat damage from a hot running component, especially given how PCB and Case are equally damaged. Not unlikely the transistor which has drossy looking solder joints (look like ...

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Trying to understand what an "address latch" is while emulating the NES PPU
0 votes

If what is being emulated is SNES functionality: The SNES used the 65816, an extended 6502 that could do 24-bit addressing - but still came in a 40 pin case which obviously allows no space for 24 ...

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How to obtain CPU and other hardware specs for emulator development
Accepted answer
12 votes

Not in all cases the schematics, parts lists, board views or even ROM assembly listings are "leaked" - it was quite common until into the 1980s to ship (or offer as an addon product) full ...

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Should 486s have a heatsink?
7 votes

Practice with actual 486-era PCs was: The non-clock doubled, sub-40MHz types (the original 486DX 20/25/33MHz) usually were neither heatsinked nor equipped with a fan. When the 50MHz (non clock ...

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Original Mac capacitor inspection
4 votes

A few generic things to know when proactively replacing electrolytic capacitors: There are at least two measuring devices you need to truly test electrolytic capacitors - a capacitance meter and an ...

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Why did CP/M and MS-DOS use the BIOS instead of their own drivers to access hardware?
1 votes

Also, there was no good support infrastructure for loading third party drivers for new hardware (released after the DOS version used) - and any loadable (or even worse TSR or firmly compiled-in) ...

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Can a retro-computer be a useful way to learn computer-architecture fundamentals?
3 votes

Yes, and countering the "still a black box" argument. Hardware on the level of the original IBM-PC or AT is accessible as an electronic system to someone with "some" electronics skills and affordable ...

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What file systems / encapsulation formats used ASCII?
0 votes

Data transmission and text file handling are not truly separate aspects in many operating systems. This is very evident in DOS and unix systems, where special files that map to character ...

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S-100 bus and device drivers
8 votes

An important thing is that old-style expansion buses - that includes S100, als well as the PC ISA bus and various proprietary buses, had no enumeration capability - a computer system was not aware of ...

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DIY Project using 1970s 8-bit CPU, is it possible?
10 votes

Custom PCBs wouldn't even be necessary, and if you want to design iteratively, could even be a hindrance. Since you will be dealing with slow rise times and a slow clock, even point or strip matrix ...

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What were practical uses of SCSI floppy drives?
13 votes

For non-PC/home computer systems (UNIX workstations, small implementations of mainframe architectures) it could have been cumbersome to use some of the existing floppy controller chips, since they ...

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80s DRAM chips: one per bit of data bus width?
3 votes

One other reason: 1-bit chips could easily be configured as 8 or 9 bit wide arrays using only one type of chip - the latter in cases where memory parity (error checking) was desired. Sometimes, 4+4+1 ...

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LCD Displays with the Intel 8080
6 votes

A passive, non multiplexed 7 segment LCD display doesn't need a real "protocol" - but neither can you just apply voltage to segments from some I/O pin. LCD displays at their core need an AC drive ...

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How did the IBM PC handle multiple physical devices serving memory at the same physical address?
6 votes

This can, in edge cases, even cause hardware damage: If you have something addressing these devices constantly (which is a plausible result from an OS/driver crash due to these ISA devices completely ...

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ZiLOG Z80 fan-out (CMOS version, Z84C0006PEC)
3 votes

74xx245 are cheap and/or can be salvaged from computer scrap (if you are capable of desoldering) in large amounts. Unless you are driving TTL circuitry, the reason you want a buffer is more about ...

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Do retro-microcontrollers exist?
6 votes

A version of the 8052 with a built in interactive BASIC (via serial port) was actually sold as an Intel product in the 1980s. Some ROM images of that interpreter can be found on the web and uploaded ...

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Where to find thermal paper for Aquarius or Commodore printer?
7 votes

Fax machines used to use thermal paper by the pallet, and it is still commonly available wherever office supplies are sold (including amazon). While this will be wider (not, as the problem is with the ...

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Is there any advantage of a ceramic microprocessor over a plastic one?
11 votes

A Ceramic/glass/metal IC housing can offer hermeticity (gas, water and sh*t proofness) satisfying aerospace/military/industrial standards, while plastics cannot do so completely - gases and liquids ...

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How do you recognize an early production model Commodore 64?
5 votes

If one wants to get an insight into when a piece of - almost any - complex electronic equipment was built, it is helpful to look for the so called datecodes on components. You will commonly find 4-...

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What was the first operating system to feature a separate kernel?
3 votes

Even an OS kernel on a some very modern system (certainly compared to what is relevant here) uses "special memory values" and machine dependent hacks to provide an ABI. https://stackoverflow.com/...

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Cost of expansion slots
2 votes

One problem adding substantial manufacturing cost and complexity when adding any socket taking edge connectors in modern hardware, especially consumer grade, is that it basically forces you to do a ...

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Is the terminal number fixed?
1 votes

These were actual serial terminals, and the tty device file very likely corresponded to a serial card - and it is likely that the kernel either had a compiled-in idea on which I/O addresses which ...

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Where can I find an external 8-inch floppy disk drive?
3 votes

Be aware that there were several incompatible formats around when 5 1/4 and 8 inch floppy disks were in use - see https://en.wikipedia.org/wiki/List_of_floppy_disk_formats. Incompatible as in, the ...

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How can a ST-412 MFM hard drive be integrated with a modern PC?
8 votes

Unless going the SCSI bridge route described in another post, you will very likely need a PC with an ISA slot - such mainboards were only common up to the Pentium 3 era, unless you are using a PC ...

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What is the oldest computer capable of running a modern version of GNU/Linux?
6 votes

The Sun sun3 architecture hails from 1985, and there are 2.6.x ports to it (which are not that different from "modern" kernels, especially when it comes to features that are useful on old hardware. It ...

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What were the 9 VAC pins used for on the Commodore 64 User Port?
5 votes

Possible uses would have been for any peripheral that needed: Its own low-noise voltage regulated power supply (eg ADC/DACs for measurement and control, or audio stuff) A symmetric power supply for ...

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Computers with integrated monitor (all-in-one form factor)
4 votes

Indeed, the PET likely took a lot of design ideas from "dumb" (actually semi-intelligent - very few of these weren't simple microcomputers inside!) terminals of the 70s, and kept the non-detachable ...

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Does the 25-pin IBM PS/1 serial port connector contain two serial ports?
1 votes

Two-in-one serial ports on DB25 have been implemented in some unix workstations, but the use of a DB25 connector on 1980s PC style computers for single serial ports was perfectly common and is not an ...

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Why do programmable sound generators like SID include a noise generator?
5 votes

There are many acoustic events - drum beats, steps, explosions, breath, abrasion, clicking... that are based on a lot of harmonically unrelated frequencies in relatively irregular patterns. Which is ...

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