[E3-hacking] pblq 0.3.pre1

David Given dg at cowlark.com
Sat Nov 29 18:53:24 GMT 2008


Dave Mills wrote:
[...]
> I've just given this version a try - no joy though. It just sits there
> "Waiting for device reset..."
> 
> I am trying to talk to a fresh out of the box E2 with a simple zener
> diode voltage limiter serial cable.  One thing that might be causing
> problems is my USB>RS232 converter - I shall have to find a laptop with
> a real serial port to try again.

Don't forget that the protocol requires the E2 to talk back. RS232 is
>+3V for logic 0, <-3V for logic 1, and the E2 expects TTL voltages with
0V for logic 0 and 5V for logic 1 --- so the sense is inverted with
respect to RS232. I don't think you can convert in both directions with
a simple voltage limiter.

I used a hacked mobile phone cable --- details on my website. I don't
think that specific model's in production any more, but once you know
what to look for RS232-TTL converters are reasonably easy to come by.

-- 
┌─── dg@cowlark.com ───── http://www.cowlark.com ─────
│
│ ⍎'⎕',∊N⍴⊂S←'←⎕←(3=T)⋎M⋏2=T←⊃+/(V⌽"⊂M),(V⊝"M),(V,⌽V)⌽"(V,V←1⎺1)⊝"⊂M)'
│ --- Conway's Game Of Life, in one line of APL

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