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Risc PC x86 Co-Processor Card FAQ

 Q.1) What is the latest version of the Emulator software?
 Q.2) Why does the serial port not work after using the card?
 Q.3) Why do Windows programs give me incorrect colours in a 256 colour mode?
 Q.4) How much memory can I configure for the PC Emulator?
 Q.5) Can I use Win95 with the card?
 Q.6) Can I resize my PC partition?

When reading this section it must be remembered that all references to the Emulator software featured in this section are to the Risc PC PC Second Processor Card controlling software, and not to the older Software PC Emulator software released by Acorn.

Q.1) What is the latest version of the Emulator software?

The latest, publicly released for all PC card owners, full version is 1.92 and it is available from the Aleph1 FTP & Web site. ( Features include memory up to 32Mb, fully redefinable 256 colour modes and the addition of directly accessed SCSI drives.

The very latest version of the software (v3.03) has been released commercially as PCPro. This features SA compatibility, speed enhancements, VESA video drivers, a debugged shared memory system for faster operation, improved support for Windows 95, DirectX drivers and a variety of other enhancements. Details of this software can be found on the Aleph1 web site.

Q.2) Why does the serial port not work after using the card?

With v1.87 of the controlling software if you choose 'Direct Serial', to enable the serial port under the emulator, and then quit the emulator it doesn't correctly release the serial port back to RISC OS. However a temporary patch is to uncomment the very last line of the !PC486.!Run file.

Run <Diva$Dir>.!RunImage
|uncomment the next line if you need to use the serial port after using !PC
| RMreinit SerialDeviceDriver

Namely uncomment the RMreinit SerialDeviceDriver so that the above looks more like this.

Run <Diva$Dir>.!RunImage
|uncomment the next line if you need to use the serial port after using !PC
RMreinit SerialDeviceDriver

Then you should find control of the serial port returned to RISC OS after you have finished with the emulator. As of v1.91 this has been fixed and the serial port will be released properly. The latest version can be obtained from the Aleph1 FTP site.

Q.3) Why do Windows programs give me incorrect colours in a 256 colour mode?

This can happen if you forgot to put a 'p' after colour descriptor in your Windows mode definition string. For example to configure the emulator to give windows a 1024x768 screen mode at 256 colours with fully programmable colours your string should look like this:-


Note the p at the end of the line.

Q.4) How much memory can I configure for the PC Emulator?

Up to v1.86 of the software the upper limit was 16 MB of memory. As of v1.87 that has been raised up to 32 MB of memory. However, for some odd reason, after 16 MB of memory the memory can be only configured in 4 MB chunks. Consequently the possible values go 1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,20,24,28 & 32 MB.

Q.5) Can I use Win95 with the card?

Yes, however the installation of it is slightly more complicated than (should be) normal for a PC. Choose a custom setup and inform the Win95 installer of what hardware you have present, under the Video driver section install the default VGA driver.

Then complete the install. Once it is installed you may then install the Arm video driver in a similar fashion as for the instructions for installing it under Windows 3.11. There are specific Windows 95 instructions for ARMDRV v1.99, this version also cures the occasional icon redraw problem with Windows95. You should then be away.

With PCPro specific Win95 installation files and instructions are provided for both the Windows video driver as well as the Sound Blaster emulation. Not to mention general instructions for installing Windows 95.

Q.6) Can I resize my PC partition?

Yes, this is possible. However the procedure is extremely risky and should not be attempted if you cannot afford to lose the contents of your partition. Ensure that you either have a backup of the partition or are prepared to possibly have to reinstall everything.

First off run Defrag on your PC to collect all the files towards the start of the partition. This is best done from DOS, doing it from within Windows 95 most likely means that the shutdown procedure will scatter a few files about potentially causing problems for resizing.

Secondly use this BASIC program to change the size of the partition under RISC OS.

REM Resize parition file.
EXT#chan=<new size in bytes>

Change the filename to suit the name of your PC partition and adjust the size in bytes to the new size of your partition. Increasing the size of the partition is safe, but when shrinking the partition care must be taken to not shrink the partition below the size of the actual files contained within it.

Finally once the partition size has been adjusted boot up your PC and run the program PRESIZER.EXE. This is a DOS partition resizer and should allow you to now adjust the partition table and FAT to the new size of your partition.

N.B. It must be stressed again that this is a very risky operation and could easily result in total data loss of your partition. Also the procedure has only been attempted for increasing the size of the partition, not shrinking it - I'd be interested in hearing from people who have attempted to shrink their partition to know if it works.

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 Last edit: 10th Apr 2016 at 4:55pm (444 days ago)

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