IPM486/IPM5 Frequently Asked Questions

PDF Manuals, Data Sheets, and Press Releases can be found in the MPL Documentation area of this homepage.

Question #223: Can I get a Manual of the IPM486?
Answer: Yes, of course, Manuals, Data Sheets and Press Releases in digital form can be requested from MPL AG.

Question #293: What operating system runs on the IPM486?
Answer: We have tested so far DOS, Windows 3.11, Windows 95, Windows NT 4.0, LINUX, OS-9000. All other OS that run on a standard PC will run on the IPM486/IPM5 as well as it is 100% PC/AT compatible. Please note that some "newer" OS like Windows XP are designed to run on processors of the "Pentium" class or better. So these OS will NOT work on the IPM486/IPM5.

Question #219: Is the IPM486 year 2000 ready?
Answer: Yes. The BIOS is checking the year byte and if it is lower than 80 (e.g. 00 for 2000), the century byte will be changed to 20 (the real time clock itself is not updating the century byte). The leap year 2000 is correctly handled. However, if an application redirects RTC interrupt 1Ah and is reading data information from CMOS register directly (not via BIOS function), it is not guaranteed that the date information is correct since in this case it is up to the application to read and update century information. Nevertheless after a system new start, it will be corrected. Please note: this is not a specific IPM486 problem, this is a general PC problem together with old software, and every PC (even the newest one) is working the same way.

Question #209: Why does the IPM486 sometimes hang after a CTRL+ALT+DEL reset?
Answer: A CTRL+ALT+DEL reset only resets the processor but no peripherals. If the G-64/96 bus was enabled before, the memory controller crashes due to a conflict with the still enabled G-64/96 VMA area. The G-64/96 bus should be disabled before a warm start.

Question #208: Does the IPM486 support 1/4 VGA panels?
Answer: Yes, but only the left upper quarter of the full screen will be shown. It is up to the user to write an appropriate application. Panels with resolutions of 640 x 480, 800 x 600 and 1024 x 768 are supported with full screen view (like a notebook computer).

Question #207: What is the fastest data rate on the parallel port?
Answer: In EPP/ECP mode up to 2Mbit/s

Question #210: What is the difference between the AMD 486DX4 and the AMD 5x86 processor?
Answer: The speed is different but the architecture is the same. You may configure the 486DX4 as a 5x86 (switch it to run with 133MHz) and it will run and be recognized by the BIOS as a 5x86, but a correct function is not guaranteed. The 5x86 runs as fast as an Intel P-75 but it has nothing to do with a Pentium processor.

Question #211: Which operating systems have been tested on IPM486?
Answer: MS-DOS 6.22, Novell DOS 7.0, Windows 3.11, Windows 95/98, Windows NT 3.51/4.0/5.0beta2, OS-9000, Linux, QNX

Question #212: Is it possible to run the IPM486 with more than 32 Mbytes of DRAM?
Answer: Yes, if the G-64/96 bus is not needed, it is possible to insert two SO-DIMM modules with 32Mbytes of DRAM each (= 64MBytes).

Question #213: Is it possible to have a Flash Disk equipped on the IPM486 with more than 8Mbytes?
Answer: Yes, a maximum amount of 16Mbytes bootable Flash can be equipped on the board. Please contact your local distributor or MPL AG.

Question #214: Why is the usable space on the equipped and formatted Flash Disk smaller than stated?
Answer: The main reason is the reserved 64kByte segment for the BIOS extension, which resides within the Flash Disk. This space is lost for applications. Another 64kByte block is left unavailable for Flash Disk data management. The operating system also occupies some of the usable area if the Flash Disk is made bootable.

Question #215: How much memory space is occupied by the Flash Disk driver?
Answer: The driver needs about 22kByte memory, but if the IPM boots from the Flash Disk (via BIOS extension), no driver is needed for any functionality (except formatting).

Question #216: Why is my Hard Disk Drive not booting correctly?
Answer: Sometimes HDD's greater than 500MB can be accessed only with an additional driver although the BIOS is able to handle it (compatibility problem). Some disks are not running correctly with the detected PIO mode. Reduce the PIO mode and try again. For some operating systems you may also change "Large Disk Access" to "Other".

Question #218: Is it allowed to run the IPM486 on a G-64/96 multi master system?
Answer: Yes, multi master functions are fully supported (including DMA on G-64/96 bus itself). However, DMA transfers between G-64/96 bus and CPU system (memory and I/O) are not possible.

Question #220: How can I access the second 128 Byte of CMOS RAM for battery buffered data storage?
Answer: If you really need to store some small amounts of data you may do so by using the second 128 Byte of CMOS RAM, which now is unused. HOWEVER, A NEWER BIOS RELEASE MAY USE THIS ADDITIONAL CMOS RAM SPACE! An access is performed by writing 88h to chipset register 55h. The chipset is accessed via index/data (22h/24h). Afterwards, every access to CMOS RAM (70h/71h) is directed to the upper 128 Bytes. Do not forget to set the CMOS access back to the lower 128 Bytes by writing 80h to register 55h.

Question #222: How are IRQ's and DMA's used?
IRQ0 Timer
IRQ1 Keyboard
IRQ2 Slave PIC7
IRQ5 Free (or G-64/96/CAN)
IRQ9 redirected to IRQ2, Free
IRQ10 Free
IRQ11 Free (or G-64/96 / CAN)
IRQ12 PS/2 Mouse
IRQ15 Free (or G-64/96 / CAN)
DMA0 refresh, redirected to 4
DMA1 Free
DMA3 Free
DMA4 Cascade input for DMA0 - 3
DMA5 Free
DMA6 Free

Note: It depends on the BIOS settings and on some applications, if more or less IRQ and DMA channels are free ore used.

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