Virtual PC

On Time RTOS-32 programs can be executed as a guest under Microsoft's Virtual PC. However, since Virtual PC does not fully emulate a real PC, some On Time RTOS-32 features may not be available or do not work as expected. On Time RTOS-32 was not designed to run on emulated hardware. Using a real target computer has none of the restrictions listed below and is therefore recommended.

The following settings are recommended if you would like to run the RTTarget-32 Debug Monitor as a guest under Virtual PC.

Create a virtual machine with at least 16M of RAM. All demo programs included with On Time RTOS-32 need 16M of RAM. With a customized .cfg file, most demos will also work with less.
To work around a bug in Virtual PC's emulated interrupt controller, apply Bootflag BF_NO_FNESTED.
Configure the virtual machine's COM1 port to be implemented as a pipe, for example "\\.\pipe\vcom". You can either use the same pipe name for the Port parameter in Rttarget.ini and use COM1 in the COMPort command. Alternatively, you can cross debug over Ethernet.
For improved download performance, instruct the Debug Monitor to execute Halt when waiting for data from the host. This is achieved using option Halt in the COMPort command.
To improve host performance, instruct your application to execute Halt when it is idle. For programs not using RTKernel-32, this can be achieved by executing:
```
RTIdleHandler = (void(*)(void))RTHaltCPL3;
```
Programs using RTKernel-32 should set RTKConfig.DriverFlags DF_IDLE_HALT and enable preemptions by setting RTKConfig.Flags flag RF_PREEMPTIVE before calling RTKernelInit.
Configure the RTTarget-32 boot code to run programs at CPL 0 using the BootFlags command. This is required because a bug of Virtual PC prevents any hardware interrupts to be delivered to a virtual machine which always runs at CPL 3. Note that running at CPL 0 is not recommended for targets other than Virtual PC.
If your program uses file I/O, configure a virtual hard disk for the virtual machine. Note that such virtual disks are initially unpartitioned and unformatted and RTFiles-32 will not mount them in this state (use Partdemo to prepare such disks).
If the program uses RTKernel-32, the default Kernel Clock driver (based on the PC Timer chip) is very inaccurate. It is recommended to use the driver combination Clkrtc.lib Hrtpent.lib (linked before Drvrt32.lib) instead.
If your program uses RTIP-32, set the Ethernet device type to DAVICOM_DEVICE and enable one network adapter in the virtual machine. If the virtual machine should come up with an Ethernet address of 00-00-00-00-00-00, copy:
```
<ethernet_card_address type="bytes">0003FF0F2E53</ethernet_card_address>
```
into the VM's .vmc file inside tag ethernet_controller with Id attribute "0".
Use Bootdisk to create a floppy boot image file of the Monitor. Boot the target from that floppy image.

An On Time RTOS-32 program executing on a virtual target does not exhibit real-time behavior. In particular, we have observed pauses of several seconds even when no other virtual machine or host program is running.

Technical support for Microsoft Virtual PC is available from Microsoft and not from On Time.

Left Running on a Virtual Target

Down VMware Workstation