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PCem V17 - Creating a VM of type 'IBM XT'

VM = Virtual Machine

STEP 1: Installation of PCem V17 into Windows 10

1.1	Create a folder named PCem under folder C:\Program Files (x86)
1.2	From here, obtain PCemV17Win.zip
1.3	Copy the files/folders from within PCemV17Win.zip into the folder created at step 1.1
1.4	On the desktop, create a shortcut that points to: C:\Program Files (x86)\PCem\PCem.exe

STEP 2: Create a VM of type 'IBM XT'

Here, we will create the VM. Adding a diskette and a hard drive to it is done later.

The VM will contain the 08/16/82 dated motherboard BIOS for the IBM XT (IBM 5160).

2.1	At here are files 1501512.u18 and 5000027.u19. Copy those two files into folder: C:\Program Files (x86)\PCem\roms\ibmxt
2.2	Use the shortcut that you created earlier. A 'PCem Configuration Manager' window will open.
2.3	Click on the button that creates a new VM. (The button at the bottom-left.)
2.4	Type in a name for the VM then click on the 'OK' button. I decided on "IBM 5160", which is reflected below.
2.5	A 'Configure PCem' window will open, allowing some configuration of the VM.

	Note that the machine type shown is '[8088] IBM XT'. It is there because of step 2.1, and because IBM XT ROM's are the only ROM's that we have placed in PCem so far, '[8088] IBM XT' is the only available machine type (i.e. no other types appear in the 'Machine:' dropdown).

2.6	For now, we will use the default configuration for the VM, changing it later. Click on the 'OK' button.
2.7	You are back at PCem's primary window. Double-click on the 'IBM 5160' line (or single-click on it then click on the button that will load it).

	The VM will start, and you will see the POST of the IBM XT's BIOS ROM displaying a RAM count-up, and then the POST will jump into Cassette BASIC.

2.8	Shut down the VM: On the menu bar, click on 'System' then 'Shutdown'. (In some cases, you may need to use a CTRL-END key combination to be able to click on 'System'.)

STEP 3: Adding a diskette to the VM

We will now simulate putting a 720K sized IBM DOS 3.3 boot diskette into A: drive.

3.1	At here is the file my_720k.ima. Copy that file into folder: C:\Program Files (x86)\PCem\roms\ibmxt
3.2	Start the 'IBM 5160' VM.
3.3	On the menu bar, select 'Disk' then 'Change drive A:'.
3.4	An 'Open' window will appear. Double-click on my_720k.ima
3.5	On the menu bar, select 'System' then 'Ctrl+Alt+Del'. (In some cases, you may need to use a CTRL-END key combination to be able to click on 'System'.)

	The VM will reboot, and you will see the IBM XT's BIOS ROM boot to A: drive.

3.7	Shut down the VM: On the menu bar, click on 'System' then 'Shutdown'. (In some cases, you may need to use a CTRL-END key combination to be able to click on 'System'.)

STEP 4: Adding a hard drive controller and drive to the VM

We will now add an XT-IDE controller and a hard drive.

4.1	At here is the modified file ide_xt.bin. Copy that ide_xt.bin file into folder: C:\Program Files (x86)\PCem\roms

	* Just to be sure: For that previous step, it is the 'roms' folder, not the 'ibmxt' folder.
	* For more information about the modified ide_xt.bin file, see the 'Additional information #2' section below.

	At this time, the 'IBM 5160' VM is highlighted.

4.2	Click on the 'Configure' button (spanner and hammer).
4.3	Click on the 'Drives' tab.
4.4	Click on the 'HDD:' dropdown then select the '[IDE] XTIDE' option.

	FYI: The '[IDE] XTIDE' option is only available because of step 4.1 The bottom half of the window is what we will use to create the hard drive for the XT-IDE controller.

4.5	To the right of 'Type:, click on the 'New' button (drive with a plus symbol). A window titled 'New Hard Disc' will open.
4.6	Change the 'Image Format:' to the option of 'Fixed-size VHD'.
4.7	To the right of 'New File:, click on the 'open-folder' button.
4.8	Type in xt.vhd then click on the 'Save' button. <---- IMPORTANT: Be sure to include typing in the .vhd bit
4.9	Click on the 'OK' button.
4.10	Acknowledge the 'Drive created' window by clicking on its 'OK' button.
4.11	Click on the 'OK' button. You are now back at PCem's primary window.

	The drive has been created, but we now have to create a DOS partition on it, then high-level format that partiton. We will do this by using the FDISK and FORMAT commands that are on the diskette in A: drive.

4.12	Start the 'IBM 5160' VM. You will see the XTIDE Universal BIOS (a.k.a. XUB) present on screen, showing the master IDE drive as 'PCemHD'. The XUB will then boot to A: (because no bootable DOS partition exists yet).
4.13	At the A:\> prompt, enter: fdisk
4.14	FDISK: Use option 1 (Create DOS partition)
4.15	FDISK: Use option 1 (Create Primary DOS partition)
4.16	FDISK: Press the ENTER key to accept the default choice of 'Y' (yes).
4.17	FDISK: Press the ENTER key. The VM will reboot.

	You will see the XUB present on screen, attempt to to boot to C:, then display "Missing operating system". That is expected in this case. You may have expected a boot to A: drive, but by default, the XUB tries C: first. "Missing operating system" is because the DOS partition on the drive has yet to be high-level formatted. We will now do that. To force the XUB to boot to A: drive, one needs to press the A key when the XUB's splash/banner text appears.

4.18	Reboot the VM. (In some cases, you may need to use a CTRL-END key combination to be able to click on 'System'.)
4.19	When the XUB's splash/banner text appears, press the A key. A boot to A: will happen.
4.20	At the A:\> prompt, enter: format c: /s
4.21	At the 'Proceed with Format' prompt, press the Y key followed by the ENTER key.

	Formatting of the DOS partition will happen, followed by the installation of some boot related files, and then the A: prompt will return.

4.22	Reboot the VM. (In some cases, you may need to use a CTRL-END key combination to be able to click on 'System'.)

	The VM should boot to the hard drive.

4.23	At the 'Enter new date ...' line, press the ENTER key.
4.24	At the 'Enter new time ...' line, press the ENTER key.

	You now have a C:> prompt.

STEP 5: Populating the hard drive

The hard drive is booting to IBM DOS 3.3, but lacks a DOS directory, and lacks AUTOEXEC.BAT
We will now copy those over to the hard drive from the A: drive.

5.1	At the C:> prompt, enter: a:\dos\xcopy a:\. /s
5.2	Reboot the VM. (In some cases, you may need to use a CTRL-END key combination to be able to click on 'System'.)

You now have a C:\> prompt, and if you enter a dir command, you will see the files and directories that you copied over.

Additional information #1

If instead of the XT-IDE controller, you wanted to install the '20MB Fixed Disk Drive Adapter' (a MFM controller) of an IBM XT:

1. At step 4.1, the file copied into the folder would be: ibm_xebec_62x0822_1985.bin
2. At step 4.4, you would select the '[MFM] Fixed Disk Adapter (Xebec)' option.
3. When creating the hard drive, use the geometry of: 615 cylinders, 4 heads, 17 sectors (i.e. IBM type 2) (i.e. the geometry expected by the '20MB Fixed Disk Drive Adapter')

I have done this in the past, and used the image format of 'Raw (.img)' for the hard drive. I named the file 'type2.img', and a copy of that file is at here.

In fact, you could add that MFM controller now, and use my type2.img file:
* Shut down the VM.
* Copy ibm_xebec_62x0822_1985.bin into the 'roms' folder.
* Copy my type2.img into the 'ibmxt' folder.
* Start the VM.
* Remove the diskette via [Disk][Eject drive A:]
* Shut down the VM.
* Configure the VM. In the 'Drives tab', change the HDD controller type to '[MFM] Fixed Disk Adapter (Xebec)', then below that, browse to select the type2.img file.
* Start the VM. You will see a boot into a 20 MB sized hard drive.

Additional information #2

At step 4.1, the file ide_xt.bin was used.
That file is the XT version of the XUB binary, where XTIDECFG.EXE was used to configure it for the controller type of 'XTIDE r1' (XTIDE rev 1).

Additional information #3

I log into Windows 10 as user Fred.

For that user account, I discovered that Windows 10 is doing some security stuff, putting the VHD and IMG files into folder: C:\Users\Fred\AppData\Local\VirtualStore\Program Files (x86)\PCem\roms\ibmxt

Additional information #4

I log into Windows 10 as user Fred.

At some point, I thought, I will use WinImage software to add some files to the my_720k.ima file in folder: C:\Program Files (x86)\PCem\roms\ibmxt
For security reasons, Windows 10 stopped me doing that.
Instead, I had to:
1. In Windows Explorer, navigate to the folder specified above in 'Additional information #3'.
2. Copy the my_720k.ima file from there to my C:\18 folder.
3. Use WinImage software to edit C:\18\my_720k.ima
4. Copy C:\18\my_720k.ima back to the folder in step 1.

Additional information #5

Do not expect PCem to do things that the real hardware cannot.