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+--- Thread: MB8328 PAK Coreboard Annoyance (/thread-291.html)
MB8328 PAK Coreboard Annoyance - someone - 05-03-2021
If you ever try to boot up to the Microbee Monitor on a microbee with an MB8328 PAK coreboard using the RESET + M sequence please be aware that the PAK circuit is a faulty design thus the RESET + M does not always take you to the inbuilt WordBee version of the Microbee Monitor.
This coreboard design uses 4042 D-type latch to hold the selected PAK value and this IC does not have a reset pin thus boots up with a random value if no battery back up is present.
Since the corresponding MWBASIC 5.22e does not write to the PAK port for a cold boot RESET + 'ESC it is not a solution.
The workaround is to know of this limitation and from MWBASIC type in PAK 0 or OUT 10,0 to select the WordBee PAK ROM which contains a microbee monitor.
It is obvious that the design flaw needed addressing and it was with versions of MWBASIC 5.25e (and later) incorporating the explicit selection of PAK Bank#5 for RESET + M attempts.
Another annoyance is that the WordBee Microsoft Monitor clears the screen and leaves a blinking cursor on the screen upon executing a 'G command.
Arrgh!