Regards:
RAM Extension Boards with Version Number v2
(Memory Self-Build-Guide 070623 or earlier)
Abstract:
There is a bad error on the Memory Extension Board. The Bug leads to a system crash when the Operating System tries to execute a program from the high memory area above 512KB. The CPU can load a program into that high RAM area - but it can not execute the code. This is caused by an erroneous signal decoding of the signals that are used to steer the access to the both 512KB RAM's. When the CPU enables the /RDROM signal to fetch the next OP-Code from the RAM, some address lines of the both RAM's IC16 and IC29 are not driven correctly (they are floating and pulled-up to +5V).
Regards:
VGA Graphic Unit
(Graphic Unit Self-Build-Guide 070704 or earlier)
Abstract:
The resistors R27, R28 and R29 have a too high value (120 Ohm) in the original design.
This leads to the effect that most of the modern TFT Displays
display only 8 of the possible 16 colors.
Bug-Fix:
To fix this problem the value of the three resistors must be reduced
to 47 Ohm. You find the resistors on the bottom-right side of the
Interface Board, near to the D-Sub connector.
Regards:
MyCPU-Tools that do not run correctly under MS Windows Vista: cpuemu5.exe, rfss.exe, etc.
Abstract:
All my software is developed and tested with MS Windows XP. The software uses
the standard 32 Bit API and should run on all MS Windows Operating Systems
up to MS Windows XP. Unfortunately the software does not run correctly under
MS Windows Vista.
Bug-Fix:
There is no Bug-Fix available. To be able to run my software on a MS Windows Vista
system you must choose the "compatibility mode" for Windows 95 or 98/ME. All other modes
won't work.
Please see this article for details.
NOTE: I will not support Windows Vista (at least not in the next few years ;-))
If there is anybody out there who can help me fixing the problems with Vista, please contact me!
Regards:
One or both of the RS232 interfaces on the Multi-I/O-Board does not work properly.
Abstract:
Depending on the populated UARTs it may happen that you get garbage printed to
the terminal screen, or you will fail to connect to the remotefs-server on com2.
Bug-Fix:
Replace all 74ACxxx -parts on the board by their 74HCxxx equivalents.
With this change it may be necessary to decrease bus speed by inserting
waitstates. Please see chapter 1.5.4 in the MyCPU self build guide for details.