Comments on: New Review - NXT Digital Sensor Ports http://nxtasy.org/2006/08/09/new-review-nxt-digital-sensor-ports/ LEGO Mindstorms NXT Blog Forums Community Downloads Tutorials Tue, 06 Jan 2009 21:02:05 +0000 http://wordpress.org/?v=2.0.4 by: Legoguy http://nxtasy.org/2006/08/09/new-review-nxt-digital-sensor-ports/#comment-108 Wed, 09 Aug 2006 19:26:47 +0000 http://nxtasy.org/2006/08/09/new-review-nxt-digital-sensor-ports/#comment-108 I've been trying to read sensor values from the US sensor for a while now, and cannot for the life of me get a valid response back from the NXT. First I'm sending this command: 00 05 03 0b 00 (which sets the sensor to LS 9v, raw mode) So far, so good. Then this, which may be incorrect, because the SDK says "R+0x03" for the last byte of the US sensor's "read measurement byte" command, and never says what R is-- does it mean literal ASCII R (hex 52 + 03 = 55)? I've had no luck trying that.. so for now I've had R = 0 (though I have tried several values for it before). 00 0f 03 03 01 02 42 03 This gives no error itself but when I go to wait for a >1 return from the lowspeed status check, 00 10 03, I get error 'dd' (communication bus error) when no program is running and occasional error '20' (pending comm transaction in progress) when a program IS running. This is the only spot where LEGO was either unclear or seems to have left out information. Critical information. No docs ANYWHERE say what R means, unless I'm completely missing something. I’ve been trying to read sensor values from the US sensor for a while now, and cannot for the life of me get a valid response back from the NXT. First I’m sending this command:
00 05 03 0b 00
(which sets the sensor to LS 9v, raw mode)
So far, so good.

Then this, which may be incorrect, because the SDK says “R+0×03″ for the last byte of the US sensor’s “read measurement byte” command, and never says what R is– does it mean literal ASCII R (hex 52 + 03 = 55)? I’ve had no luck trying that.. so for now I’ve had R = 0 (though I have tried several values for it before).
00 0f 03 03 01 02 42 03

This gives no error itself but when I go to wait for a >1 return from the lowspeed status check, 00 10 03, I get error ‘dd’ (communication bus error) when no program is running and occasional error ‘20′ (pending comm transaction in progress) when a program IS running.

This is the only spot where LEGO was either unclear or seems to have left out information. Critical information. No docs ANYWHERE say what R means, unless I’m completely missing something.

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