Disruptor wrote on 2021-06-29, 19:06:The key with the busmaster transfers is that the main processor could so something else while data is transferred from disk to m […]
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The key with the busmaster transfers is that the main processor could so something else while data is transferred from disk to memory or vice versa.
However, this requires a multitasking operating system. You won't see much improvement on DOS.
Yes there are some PCI IDE or even SATA controllers. Some of them may not work in a 486 due to old PCI version, Pentium commands in BIOS, ACPI calls or something else. You may try. On VLB it is even more difficult. There are Adaptec 2840VL and 2842VL. But it may happen that your VLB board is incompatible to your busmaster controller. And it may happen that busmaster controllers do not run in every slot - you have to try.
I've upgraded my 386sx/20:
Original configuration
8 MB RAM
IDE controller
520 MB IDE disk (capped to 504 MB) (PIO 3)
ISA ET4000 AX
New configuration
20 MB RAM (4 MB EMS which is only usable under DOS)
Adaptec 1542B
1 GB SCSI disk
ISA ET4000 W32
I know a 386sx is a kind of torture under Windows 95, but with a GUI accelerator and a busmaster storage controller it became a little beast!
Nice! You have my respect and I adore you, haha. Yes, I love the 386 for old games like Gunboat. They are better playable than on 486 (even with turbo off). So I want to push the I/O operations throughput to max, but keep the CPU cycles original.
Mine is 386DX-40 + coprocessor and it came preinstalled with Win95 and CD-Rom (connected to Sound Card). It is currently my favourite machine for DOS gaming. I win it in some auction locally and it was a company computer (that's why Win95).
I have also ISA ET4000 W32, but it has some compatibility issues. For example in Chaos Engine it does not work. Even in SETUP I switch from VGA to TSENG (they have some fix) and it does not work. It originally came with Trident 1MB ISA, but I could see some ghost 5px x 5px semi transparent mosaic (maybe reflow framebuffer like 3dfx haha). So I bought Octec AVGA-20 (Cirrus Logic) and now everything works perfectly. It came with 512kb only, but I have stolen the 256kb 60ns memory from Trident and now it has 1MB as well.
I upgraded with ZIP 250 MB and FlashFloppy USB emulator (GoTEK mod). I will upgrade more, perhaps SCSI. Right now I have GSI Model 21 IDE controller, which supports 4 floppy drives and 2 IDE drives. But in the end I might not need it for this machine because I bought 5.25'' + 3.5'' floppy combo drive. The plan now is to put ISA ethernet with XT IDE (ready to go) and I need to partition 32GB SD, so it can run DOS 6.22 + Win95 + FreeDOS. Mainly for experimenting with software and fixing compatibility issues on the go.
Cherry on top will be ISA USB card (found on AliExpress) and I will upgrade this 386 to WiFi, hehe. There is Ethernet RJ-45 to Wifi bridge. So you can "wifilize" any ethernet device and even 286 can have Wifi 😁. I found also ISA EIDE controller, which should provide faster speeds.
These are my upcoming upgrades:
1) https://www.ebay.com/itm/114861659090 (must have 386 sticker for chassis hehe)
2) https://www.ebay.com/itm/274813297018
3) https://www.ebay.com/itm/184367485595
Cherries on top:
- Teensy controller for active USB HID to AT DIN (I'm running Ajazz K510 retro styled modern USB RGB mechanical keyboard)
- OSSC VGA scanliner to HDMI connected to Samsung QLED TV (the side effect is that you are able to connect Bluetooth headset to TV and have wireless audio)
- FreeDOS has a lot of new drivers that makes it possible to use different hardware easily (networking features, FAT32, HX RT DOS Extender can run simple Win32 apps - need to test it)