China DOS Union

I have made an IMG - type image that can be booted in VMware (booting to A:\) which is at most 4M (4320K). If it is larger (expanded by WinImage), VMware says there is an IO read - write error.

Now I want to make a 10M or so img floppy boot image that is supported by VMware, and I don't know how to do it.

Which friend can provide the method or give me a ready - made such large image for reference.

Thanks...

The BIOS specifies that the floppy drive cannot exceed 2.88M. It's a miracle that you can use up to 4.32M.

4M shouldn't be considered a miracle. My PM8.5 server image is 4M and I've been using it for two years. It works fine when directly called in VMware and also fine when called with EasyBoot (VM or burned to disc and run on a real machine).

Originally posted by Coolie at 2009-5-18 11:15 PM:
4M shouldn't be considered a miracle. My PM8.5 server image is 4M and has been used for two years.
It works fine when directly called in VMware, and also fine when called with EasyBoot (VM or burned to disc for running on a real machine).

EasyBoot uses its own floppy drive emulation function without the 2.88MB limit
While the virtual machine's img uses the floppy drive reading and writing function in its own BIOS. According to the floppy drive standard, it can be at most 2.88MB

I copied that 4M image to a 32M old USB flash drive using WinImage, and it can be normally booted and used for maintenance as USB-ZIP. Now it's not about discussing this image. I want to ask why when it's larger than this image, it can't be emulated to boot as A:\, including in EasyBoot, it can only be emulated to boot as C:\, and I hope to emulate it as A:\.

Originally posted by Coolie at 2009-5-19 06:38 AM:
I wrote the 4M image to a 32M old USB flash drive using WinImage, and it can be normally booted and maintained as a USB-ZIP.

Now it's not about discussing this image. I want to ask, why can't it be simulated as ... when it's larger than this image...

Because a: is a floppy drive, and the standard floppy drive is only up to 2.88MB at most, so the BIOS can support at most a 2.88MB floppy drive. VMware is a virtual machine, and the BIOS standard is completely made according to the real machine.

As for easyboot, it simulates the img as a:, not directly accessing a: through the BIOS, so it can support larger images

Expert高手 upstairs, please come to this address first to play with my PM8.5 image.

http://www.brsbox.com/filebox/down/fc/1112655b75b006a0aaa3cb1bfaf28be6

PM8.5 boot img image, the image body is 4M (compressed package is 2.79M), simulated as A:\. Supports direct call by VMware (no need for Easyboot call), supports USB-ZIP simulation, and of course supports Easyboot call.

Please don't use Easyboot, but directly set a virtual OS in VMware, then add a virtual floppy drive pointing to this image. Just enable Floppy support in the VM's Bios, whether it is set to 1M disk support or 2M disk support format, let's see if there is a problem when calling this image?

After testing, it is found that the VM floppy drive has a 2.88M limit.

Supplement:
1. According to my short experience with VM, the floppy drive format set in the VM's Bios is affected in that if you set the virtual floppy drive to point to a physical floppy drive instead of an image. If it points to an image, it is not affected by the format specified here (unless you specify the virtual floppy drive as none, then it is affected).
2. The reason why I raised the question on the roof is because I once downloaded a dozen M image in VM and could directly call it to simulate as A:\. At that time, I thought it was simple, thought it was the same principle as making a small image, and at that time I had no urge to make a large image, so I didn't keep that image file. Now I want to make a large image and encounter problems, and I can't find that image anymore (the worst is that I even forgot the name, so the search engine has been flipping for a long time without results), so I came to this forum to post for help.

Here I am not challenging the ability of the upstairs master, maybe I am not qualified enough. First of all, thank the upstairs master for the many enthusiastic replies, but I am here to find the method to solve the problem, not to wait for the reply of "this is not supported, that is not possible". Thank you...

Originally posted by Coolie at 2009-5-20 11:08 AM:
Dear expert above, please first come to this address to play with my PM8.5 image.

http://www.brsbox.com/filebox/down/fc/1112655b75b006a0aaa3cb1bfaf28be6

PM8.5 starts the img image, the image body is 4M (compressed...

The IMG made with ULTRAISO with a size of 3.84 can start DOS normally in VM, but the one with 5.76MB cannot, and it can be booted normally with EASYBOOT.