6 ms·
This is the kind of spring cleaning I crave. Deleting busted drivers that haven't worked in over a decade? Fantastic! Some of this hardware likely has exactly
by bastawhiz 6mo ago
This is the kind of spring cleaning I crave. Deleting busted drivers that haven't worked in over a decade? Fantastic!
Some of this hardware likely has exactly zero users because the material it's made from can't possibly have survived. Look at the cord on the mouse in the photo: you might be able to plug it in, but I wouldn't bet money signal can still make it down the wire.
- trollbridge 6mo agoMy bus mouse still works just fine; things built in the 80s tended to be pretty solid. However, it would be hard pressed to find a machine with ISA slots with enough resources to run Linux 7.1 acceptably.
- cestith 6mo agoThere are still ISA slots in new systems with fairly modern processors and plenty of RAM, if you don’t mind buying specific models of industrial PCs for way too much money. For $1100 or so you, too, could have a 4th generation Core i3 machine. https://www.rampcsystems.com/product/2-isa-slot https://www.rampcsystems.com/product/2-isa-slot Or maybe you need 4 PCI and 9 ISA for some reason. DuroPC’s got you, if you can drop $1800 on a system with the same generation of processor. https://duropc.com/product/r810-4p9i-4 https://duropc.com/product/r810-4p9i-4
- M95D 6mo agoISA slots are all identical. If you have one slot, you can multiply it to 100 slots just by connecting the wires.
- cestith 6mo agoThat’s one of those facts that’s always good to know, but in practice people tend to put one card in one slot with no expanders.
- SV_BubbleTime 6mo agoHow were different devices addressed? I assume it’s a master and slave system, but even then were address collisions automatically resolved?
- stackghost 6mo agoThey used 16-bit addresses from 0x0 to 0xffff.
- toast0 6mo ago> How were different devices addressed? There's a shared address bus. Each device responds to the i/o and/or memory addresses it's configured for. Configuration can be static, jumpers, isapnp. > I assume it’s a master and slave system, but even then were address collisions automatically resolved? No. If two devices want to use the same address space, you'll have problems. isapnp might help you out, but it was added in the second decade of ISA, so ... lots of things don't use it.
- tialaramex 6mo agoIn original ISA none of this is managed, the owner of the PC is expected to manually configure both hardware and software appropriately. So e.g. [with the PC turned off!] you move a tiny jumper (basically just a piece of conductive metal with a plastic housing) to the "IRQ 8" position and you pick "IRQ 8" in some menu or set it in an environment variable in DOS or whatever. By the time PCI is starting to appear there is some level of "Plug and Plug ISA" but it's fairly crazy because of course all the old stuff still exists whereas for PCI the bus always had this intelligence baked in so nobody just assumes they can pick.
- M95D 6mo agoIt can't be IRQ 8 on an ISA board. That's the IRQ for the RTC.
- tialaramex 6mo agoThat's correct. I considered whether I should dig out a manual and decided that I should do the exact opposite and pick a value I know won't exist for ISA.
- stackghost 6mo agoI'm pretty sure the host will run out of IRQs long before 100. Don't most systems only have 16?
- M95D 6mo agoYou don't really need IRQs for most ISA boards. OPL3/Adlib sound cards don't need one, MIDI doesn't, joystick port doesn't. I saw various I/O boards that don't need IRQ. Soundblaster does, but I don't know for what purpose. Maybe someone here can explain?
- stackghost 6mo agoSound Blasters and compatible cards used IRQ lines because back in the bad old days CPUs were slow, bandwidth was tiny, and buffers were minuscule. To get responsive/real time audio the card needs to signal to the CPU, not the other way around, and at the time IRQs were the way to do that on ISA busses. I would imagine that ISA cards that didn't need IRQs either required CPU polling or DMA.
- M95D 6mo agoI imagined that the game / audio driver would just send data to the card at regular intervals and that's it. I realize now that the card uses it's own clock that can drift when compared to the system timer and this method would have a buffer underrun/overrun problem.
- jpernst 6mo agoCoincidentally I'm currently working on a Sound Blaster driver for some DOS homebrew, so here's quick rundown of how an SB is programmed and what its resources do: Base Address: This is the beginning of the IO port range you use to program the card, commonly it's 0x220, but can be configured with jumpers (or software on later cards). You can add offsets to this address to access different functionality of the card, such as the OPL chip or the Mixer chip. IRQ: The interrupt number that will be fired when the soundcard finishes playback of an audio chunk. Early cards usually used 7, later models defaulting to 5. More on this below. DMA Channel: Which channel of the PC's DMA controller will be supplying audio data to the card. Usually 1 for 8-bit cards, with 5 being used for 16-bit cards. The general process for playback is as follows: - Program the DMA controller with the address and size of an audio buffer you'll be using to mix your PCM sound into. This buffer will conventionally be used in 2 halves by the interrupt service routine, a front buffer and backbuffer, similar to what you'd have for double buffered video. The DMA channel should also be put in "auto-init" mode so that the DMA transfer will loop back to the start when it finishes, which allows continuous playback. - Install an interrupt service routine to write data into the "backbuffer" half of the DMA buffer, which switches back and forth each time an IRQ fires. - Initialize the DSP chip via its IO port, pick a sample rate (usually around 11khz for most DOS games), then issue a continuous playback command. For this part, you tell the soundcard that your playback buffer is half the size it actually is, which causes the IRQ to fire once in the middle of the buffer, and again at the end of the buffer before looping back to the start. These halfway IRQs allow you to fill the unused half of the buffer while the other half is playing, for smooth gapless playback with no clicks or pops. This is probably more info than you or anyone actually wanted, but it's a fun topic so I couldn't help myself.
- bitwize 6mo agoThis is what the word "bus" used to mean on a hardware level: a backplane of connections to which multiple peripherals could be attached. These days a bus is a LAN of point-to-point serial connections which, it turns out, is much more viable at the high communication rates demanded of modern hardware.
- satiated_grue 6mo agoThere was at least one non-identical ISA slot: https://www.lo-tech.co.uk/wiki/IBM_Personal_Computer_XT_System_Board_Slot_8 https://www.lo-tech.co.uk/wiki/IBM_Personal_Computer_XT_Syst... https://www.lo-tech.co.uk/understanding-pcxt-slot-8/ https://www.lo-tech.co.uk/understanding-pcxt-slot-8/
- M95D 6mo agoIBM was always special. :-) Aren't they the ones who invented the MCA bus abomination that required a floppy disk to configure each card?
- trollbridge 6mo agoYou may want to read up on the history of dip switches, jumpers, and plug and play a little bit more.
- cestith 6mo agoI used to have a couple of IBM EduQuest machines. The majority of the ISA slots were wrong-handed.
- estimator7292 6mo agoMost things. Plastics and rubbers tend to not survive well a lot of the time just because of the chemistry. There's really no way around plastic embrittlement and rubber decomposing. You can prolong it with the right storage conditions, but those molecules are gonna break down sooner or later.
- dpark 6mo ago> things built in the 80s tended to be pretty solid Survivorship bias. We built a lot of crap stuff in the 80s, too. Most stuff built in the 80s is probably in landfills now.
- Incipient 6mo agoI don't know how you'd confirm either way. A lot of stuff from the 80s is in landfill now because it's just old, even if not broken. I'm sure we built a lot of badly made stuff then too, but my guess is with our tighter manufacturing tolerances, we can push things closer to breaking point, with our increased casting/molding tech, we make stuff smaller and more complex, so it breaks more, we also drive harder to profit margins (unsourced claim!) so cutting corners/quality is more acceptable/planned obsolescence/planned failure.
- FpUser 6mo agoMy Z840 server I use for self hosting has both bus original IBM keyboard and bus mouse attached. Either works just fine.
- kube-system 6mo agoThe mouse in the photo was made somewhere between 1987-1993. I have computers older than that which work just fine.
- kstrauser 6mo agoSame, but I didn't spend a lot of time putting my grubby hands on those computers.