Triage update: I was very careful collecting data on the new PCB using a non-invasive analysis technique. Data confirms the readout pins are damaged (ie intentionally by the manufacturer) on all three chips of interest: AA-013 (8741) AA-016 (8041AH) AA-017 (8041AH)
I tried to read data out anyway and was unsuccessful (this worked on at least one chip previously).
With that in mind, this is the strategy moving forward. 8041AH can be read out optically, although its a bit noisy. However, we have several sets now (2 or 3 in inventory) which should dramatically improve accuracy. We'll sort through the data we already have and collect new data as necessary.
Note some preliminary data indicates there may be 8041AH ROM variants, but this needs to be confirmed. If so it will be addressed at that time.
Short term focus will be on 8041AH since it has a relatively straightforward path to generate dumps. 8741 will likely require microprobing which we are able to do. Unfortunately the pad driver is relatively complex. If someone is interested in analyzing the 8741 die, especially around EA, it would significantly help that project. Otherwise we plan to adopt a "guess and check" probing strategy on a sample chip which may also work.
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