[ot][spam][crazy] The Trials of Controlling a Programmer

[Undiscussed Horrific Abuse, One Victim of Many]

I'm still trying to figure out this oscilloscope (dso nano) which I think
needs a firmware update.

I'm looking at a log of CLK from the voltage divider connected to my
raspberry pi. The chart goes off the display and it says the peak-to-peak
voltage is 33.6V .  It goes off the display in both the positive and
negative directions.

A raspberry pi usually produces no more than 5V, so this is some electrical
thing. I don't know a lot about electronics, but they're full of noise and
stuff.

On Tue, Apr 5, 2022, 7:15 AM Undiscussed Horrific Abuse, One Victim of Many
<gmkarl at gmail.com> wrote:

>
>
> On Tue, Apr 5, 2022, 7:02 AM Undiscussed Horrific Abuse, One Victim of
> Many <gmkarl at gmail.com> wrote:
>
>> notes: in the flasher source, it's designed for more than one interface,
>> and use of the lpc chip is guarded by this:
>> uint8_t lpc_test(void) {
>>         nibble_hw_init();
>>
> FRAME is driven high for 1us and then allowed to drop for 1us.
>
>>         lpc_init();
>>
> calls nibble_init():
> INIT is briefly dropped and then raised.
> CLK is raised.
> FRAME is raised.
> calls nibble_write(0):
> DATA lines are set high.
> calls clock_cycle() 24 times.
> The code for clock_cycle drops CLK then immediately raises it.
>
> It goes on with more port writes. I may have made an error in transcribing
> the above.
>
> I'm guessing the clock is happening faster than I have my oscilloscope
> set. Maybe I can spend some time learning it better and see the 1us FRAME
> behavior.
>
>         if (lpc_read_address(0xFFFFFFFF)==-1) return 0;
>
>>         return 1;
>> }
>>
>> flashrom itself doesn't seem to care about that check (although I haven't
>> looked in the source): it just probes for a bunch of chips anyway.
>>
>> so I guess the thing to do would be to look for the first lines that are
>> engaged, and see where failure starts.
>>
>
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