I would not say never. But when I did some programming I always built in the "user error" options....it's like designing a fuse into an electronic circuit....
You need not explain to me the importance of "user error" options; this is why the flashing tool signature checks the firmware components and will not allow the user to flash the wrong file to the wrong slot. Regarding the CPLD question specifically, however, circumventing user... oversight, shall we say... is not so easy. Firstly the extra IO RAM opened up by the v2 JED is completely inaccessible outside of the BIOS setup utility unless the PBI BIOS is enabled. With the PBI BIOS enabled, we can at least probe $D1FF (much the same as the manual method I suggest for checking the existence of the math pack overlay), although having the PBI BIOS enabled is in no way a pre-requisite for flashing the ROM.
The best I can offer here is a warning message when updating the BIOS from the legacy version to the alt version, along the lines of "Please go and figure out if you have the V2 JED first".
Could you explain these steps a bit more?
This is interesting. I would like to know how to do these steps, so I can check which U1MB's are v1 (I am sure I have at least 3 of these)
Remove any external PBI devices, enable "SIDE hardware" and "SpartaDOS X" using the original BIOS. Ensure the SIDE PBI ID is set to "1". Boot into SDX. Type:
This clears the prompt and ensures no SIO activity while we're typing commands. Type:
Note the result. Type:
Note the result (hopefully "U"). If the peeked value changed, you have the V2 JED (since we know the math pack overlay just appeared). We can go further and look for RAM at $D1xx and $D5xx too, but there should be no need.
Alternatively, one can just plug in SIDE, enable SIDE hardware, and see if the HDD works. But the above instructions are intended for non-SIDE owners. Note also that if the "SIDE hardware" option is present on a board with a V1 JED, it means the board has the wrong BIOS anyway. The difference is that alt BIOS requires the V2 JED to boot.
Generally, the existence of the "SIDE Hardware" option on the legacy BIOS menu is an indication that you're good to go.
Edited by flashjazzcat, Fri Sep 22, 2017 5:34 AM.