Say I just want to buy some servos..

[Robo1]

A quick question:

what resolution are you guys seeing with say 7 servos in a chain. writting position to each and reading the data e.g. position force. this is with nothing else runnig o the proc apart from these commands.

I want to know as I'm going to start righting a closed loop system for my DX-117 and what to know the res any thing above 200/s would make me very happy.

cheers bren

[JonHylands]

Well, the refresh rate you will get will be different than what we can get. The DX-117 uses RS-485, and I have no idea what controller you're using or how it communicates with a PC.

However, since the DX-117 uses the same type of command language, talking to 7 servos and getting the 3 values back from each, 200 times per second would take a minimum bandwidth of about 340 Kbps.

- Jon

[Robo1]

that sounds good. will be using the CM-2 for the time being (have one on order) then will make my own controller. As the DX can run at 1Mps should be able to run at least 400 loops per sec which should make for a pritty good control system.

thanks bren

[billyzelsnack]

Hmm. I'll check into the 56k max. If that's the case then I think I'll be doing some USB to 485 research tonight.

[billyzelsnack]

hmm. Page 114 of the users guide shows the same baud table that the ax-12's has.

"The baud command changes the baud rate of the CM-5 itself and all the Dynamixels that are connected to the CM-5"

Sounds promising. Now I just need to figure out how to send/receive data. Seems easy enough to sniff considering you can see exactly what is happening with the terminal program. Though maybe you can and I just have not found out where it tells me how to yet.[/img]

[billyzelsnack]

I could not get any serial sniffers to work under Vista. I'll try on XP tomorrow.

I did verify that a regular old terminal emulator will work in place of the 'robot terminal' program.

I'll need to get a sniffer working before I can go much further. I was messing with sending in 'program' and 'play' mode. Sometimes a 'go' command would work at a slow speed, but it would only work once. There are probably a bunch of codes that can do various things that I'll need to know.

hmm. Maybe I should look around and see if anyone else already has done this work.

[billyzelsnack]

Ok. Here's the first sniff result. It goes TX RX TX RX etc. This is from going into the behavior program and downloading an example (not the motion) and telling it to play. Then I hit start on the CM-5 and it goes. I don't think all of that is visible in the log though.

--------------------------

Recorded and exported to HTML by SmartSniff.

HEADER INFO INTO FILE C:\Users\billy\Documents\Default.mpsl
File version: 4.30
Max supported version: 4.30
PORT - COM


Speed switching: #1
BaudRate=57600
Parity=0
StopBits=0 (1 bit)
ByteSize (bits)=8
As binary (DCB)=1C 00 00 00 00 E1 00 00 01 40 00 00 00 00 64 00 64 00 08 00 00 11 13 00 1A 00 00 00


000000 (00000), 0 ms

2A 2A 2A ***



000001 (00000), 203 ms

02 02 02 ...



000002 (00001), 2406 ms

2A 2A 2A ***



000003 (00001), 2609 ms

02 02 02 ...



000004 (00002), 2609 ms

23 23 23 23 23 23 23 23 23 23 23 23 23 23 23 23 ################
23 23 23 23 23 23 23 23 23 23 23 23 23 23 23 23 ################
23 23 23 23 23 23 23 23 23 23 23 23 23 23 23 23 ################
23 23 ##



000005 (00002), 2813 ms

02 02 02 FF ....



000006 (00003), 2813 ms

23 23 23 23 23 23 23 23 23 23 23 23 23 23 23 23 ################
23 23 23 23 23 23 23 23 23 23 23 23 23 23 23 23 ################
23 23 23 23 23 23 23 23 23 23 23 23 23 23 23 23 ################
23 23 ##



000007 (00003), 3016 ms

0D 0A 0A 20 53 59 53 54 45 4D 20 4F 2E 4B 2E 20 ... SYSTEM O.K.
28 43 4D 35 20 42 6F 6F 74 20 6C 6F 61 64 65 72 (CM5 Boot loader
20 56 31 2E 33 31 29 0D 0A 20 2D 20 23 23 23 23 V1.31).. - ####
23 23 23 23 23 23 23 23 23 23 23 23 23 23 23 23 ################
23 23 23 23 23 23 23 23 23 23 23 23 23 23 23 23 ################
23 23 23 23 23 23 23 23 23 23 23 23 ############



000008 (00004), 3219 ms

0D 0D ..



000009 (00004), 3422 ms

0D 0A 20 2D 20 0D 0A 20 2D 20 .. - .. -



00000A (00005), 3422 ms

0D 6C 64 20 61 30 30 30 0D .ld a000.



00000B (00005), 3625 ms

0D 0A 20 2D 20 6C 64 20 61 30 30 30 0D 0A 20 57 .. - ld a000.. W
72 69 74 65 20 41 64 64 72 65 73 73 20 3A 20 30 rite Address : 0
30 30 30 41 30 30 30 0D 0A 20 52 65 61 64 79 2E 000A000.. Ready.
2E .



00000C (00006), 3625 ms

04 06 04 E4 02 06 04 05 04 80 00 C8 20 00 04 08 ............ ...
00 00 01 04 4E 00 81 00 C8 20 00 04 02 00 00 01 ....N.... ......
04 F9 00 81 00 C8 20 00 04 01 00 00 01 04 46 01 ...... .......F.
81 00 C8 20 00 04 04 00 00 01 04 A8 01 81 00 C8 ... ............
20 00 04 10 00 00 01 04 C7 02 01 04 09 00 02 00 ...............
64 29 04 FF 00 02 00 64 28 04 00 00 02 00 C8 18 d).....d(.......
04 14 00 06 04 18 04 02 00 C8 18 04 15 00 06 04 ................
18 04 02 00 C8 18 04 16 00 06 04 18 04 06 04 34 ...............4
04 02 00 64 25 04 00 00 80 00 64 25 01 04 00 00 ...d%.....d%....
00 01 04 A6 00 80 00 64 1B 02 04 32 00 00 01 04 .......d...2....
EA 00 01 04 88 00 02 05 00 00 00 64 25 02 00 C8 ...........d%...
18 04 14 00 06 04 18 04 03 05 00 00 05 00 00 01 ................
04 01 00 02 00 C8 18 04 15 00 06 04 18 04 80 05 ................
00 00 01 04 00 00 00 01 04 B8 00 02 00 C8 18 04 ................
16 00 06 04 18 04 01 04 81 00 02 00 C8 18 04 17 ................
00 06 04 18 04 01 04 81 00 02 00 64 29 04 FF 00 ...........d)...
02 00 64 28 04 04 00 02 00 C8 18 04 28 00 06 04 ..d(........(...
18 04 80 00 64 1B 02 04 32 00 00 02 00 C8 18 04 ....d...2.......
29 00 81 00 64 1C 02 04 50 00 00 02 00 C8 18 04 )...d...P.......
2A 00 81 00 64 1A 02 04 50 00 00 02 00 C8 18 04 *...d...P.......
2B 00 01 04 12 01 02 00 64 29 04 FF 00 02 00 64 +.......d).....d
28 04 01 00 06 04 34 04 80 00 C8 18 00 04 0B 00 (.....4.........
00 02 00 C8 18 04 0E 00 82 02 00 C8 18 04 0C 00 ................
06 04 18 04 02 00 64 25 04 00 00 80 00 64 25 03 ......d%.....d%.
04 03 00 00 01 04 7B 01 80 00 64 1B 03 04 C8 00 ......{...d.....
00 02 00 C8 18 04 0D 00 82 02 00 C8 18 04 0B 00 ................
06 04 18 04 01 04 58 01 02 00 64 29 04 FF 00 02 ......X...d)....
00 64 28 04 03 00 02 05 01 00 04 64 00 06 04 3B .d(........d...;
02 02 00 C8 21 04 18 00 06 04 26 04 80 00 64 1B ....!.....&...d.
02 04 32 00 00 01 04 FB 01 80 00 64 1A 02 04 3C ..2........d...<
00 00 01 04 2B 02 80 00 64 1C 02 04 3C 00 00 01 ....+...d...<...
04 33 02 06 04 57 02 01 04 CC 01 06 04 73 02 02 .3...W.......s..
00 C8 21 04 10 00 06 04 26 04 80 00 64 1A 02 04 ..!.....&...d...
32 00 00 06 04 8F 02 82 06 04 AB 02 02 00 C8 21 2..............!
04 10 00 06 04 26 04 01 04 CC 01 06 04 8F 02 01 .....&..........
04 CC 01 06 04 AB 02 01 04 CC 01 80 05 01 00 05 ................
04 00 00 00 06 04 11 04 02 00 C8 18 04 4E 00 02 .............N..
05 01 00 04 00 00 07 80 05 01 00 05 04 01 00 00 ................
06 04 11 04 02 00 C8 18 04 3C 00 02 05 01 00 04 .........<......
01 00 07 80 05 01 00 05 04 02 00 00 06 04 11 04 ................
02 00 C8 18 04 45 00 02 05 01 00 04 02 00 07 80 .....E..........
05 01 00 05 04 03 00 00 06 04 11 04 02 00 C8 18 ................
04 57 00 02 05 01 00 04 03 00 07 80 05 01 00 05 .W..............
04 04 00 00 06 04 11 04 02 00 C8 18 04 60 00 02 .............`..
05 01 00 04 04 00 07 02 00 64 29 04 FF 00 02 00 .........d).....
64 28 04 02 00 02 00 C8 18 04 18 00 06 04 18 04 d(..............
01 04 09 00 80 00 01 08 00 04 00 00 00 02 00 01 ................
08 04 FF 03 80 00 02 08 00 04 00 00 00 02 00 02 ................
08 04 FF 03 80 00 03 08 00 04 00 00 00 02 00 03 ................
08 04 FF 03 80 00 04 08 00 04 00 00 00 02 00 04 ................
08 04 FF 03 80 00 05 08 00 04 00 00 00 02 00 05 ................
08 04 FF 03 80 00 06 08 00 04 00 00 00 02 00 06 ................
08 04 FF 03 80 00 07 08 00 04 00 00 00 02 00 07 ................
08 04 FF 03 80 00 08 08 00 04 00 00 00 02 00 08 ................
08 04 FF 03 80 00 09 08 00 04 00 00 00 02 00 09 ................
08 04 FF 03 80 00 0A 08 00 04 00 00 00 02 00 0A ................
08 04 FF 03 80 00 0B 08 00 04 00 00 00 02 2A 2A ..............**
2A *

[billyzelsnack]

Well look at this!

http://robosavvy.com/modules.php?name=F ... opic&t=305

Someone already started looking down this route back in May.