Baudmode for connecting to a Romba's SCI

Frohman

HELP I can't figure our how to calculate the proper baudmode...

The device is an IROBOT Roomba, and I am trying to connect to it through it's SCI (Serial Command Interface).
the documentation for connecting is here: www.irobot.com/images/consumer/hacker/Roomba_SCI_Spec_Manual.pdf

The roomba I am connecting to is 57600 baud, 8-bit with no parity and I dont know if it is inverted or not... they don't say... so I am guessing it is not inverted... (because you need to make a special cable with a protoboard to control the roomba from a pc)


need some help here.

P.S. I am using a BS2

SSteve

According to the SERIN documentation in the Basic Stamp Command Reference, the BS2 can only go up to 50k baud. To get to 57600 you need a BS2sx or BS2p.

Edit: The baud mode for 57600 on the BS2sx or BS2p is 23. That's int(2500000 / 57600) - 20.

▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
OS-X: because making Unix user-friendly was easier than debugging Windows

links:
My band's website
Our first album on the iTunes Store
Our second album...

Frohman

your wrong this is not hopeless... the Roomba can be forced to switch to 19200 baudrate!

edit: darnit i Forgot how to set pins to low and high cause I need to do that to turn it to 19200 baudrate

Post Edited (Frohman) : 7/12/2010 9:13:29 PM GMT

SSteve

Sorry, I didn't look at the Roomba doc so I didn't realize it could be switched to 19200. Doesn't look like you need to set any pins high or low, just hold the power button for five seconds.

▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
OS-X: because making Unix user-friendly was easier than debugging Windows

links:
My band's website
Our first album on the iTunes Store
Our second album...

Peter KG6LSE

YAY A roomba hack! . I have done this a few times in past years . [noparse]:)[/noparse] It was one of the reasones I got HWB BS2 many years ago .
On the DIN plug If you pull PIN 5 DD/wake low 3 times it will also do a Baud change .. Its on page 2 of the PDF .
Peter KG6LSE

▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
"Carpe Ducktum" "seize the tape!!"
peterthethinker.com/tesla/Venom/Venom.html
Never underestimate the bandwidth of a station wagon full of tapes hurtling down the highway. —Tanenbaum, Andrew S.
LOL

Frohman

[noparse][[/noparse]sarcasm] NO WAY! [noparse][[/noparse]/sarcasm]

what the heck is the proper baudmode...
INT(1,000,000/19200)-20 = 32?
so it's this?

HIGH 
SEROUT 3, 32, 128 'stop normal opperation - "start" command
SEROUT 3, 32, 130 'put Roomba in SafeMode - "control" command
SEROUT 3, 32, 135 'make the roomba clean and then wait for more instructions - "clean" command

and later on...

SEROUT 3, 32, 133 'turn roomba off

▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
MAGGOTS!

Post Edited (Frohman) : 7/13/2010 2:16:25 AM GMT

Peter KG6LSE

tie the din 5 pin to BS2 pin 2
Rough code ..mod to your Pin liking i nomaly make 1 IN and 0 Out and 2 DD

Gosub  intbuad

YOUR   CODE  HERE

'GOSUBS

intbaud:'  sets    pin 2 on BS2  low  3   times 
High 2 
pause  300
low  2          ' X1
pause 250 
high  2
pause 300
low  2           'X2 
pause 250 
high  2 
pause 300
low 2           'X3 
pause 250 
high  2 
pause 300
return '  returns    to  MAIN prog 

Peter KG6LSE

▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
"Carpe Ducktum" "seize the tape!!"
peterthethinker.com/tesla/Venom/Venom.html
Never underestimate the bandwidth of a station wagon full of tapes hurtling down the highway. —Tanenbaum, Andrew S.
LOL

Frohman

this... is odd... I dont understand why you would use a subroutine. Because this would be the first thing you do in your code...

Peter KG6LSE said...

Gosub  intbuad

YOUR   CODE  HERE

'GOSUBS

intbaud:'  sets    pin 2 on BS2  low  3   times 
High 2 
pause  300
low  2          ' X1
pause 250 
high  2
pause 300
low  2           'X2 
pause 250 
high  2 
pause 300
low 2           'X3 
pause 250 
high  2 
pause 300
return '  returns    to  MAIN prog 

Peter KG6LSE

▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
MAGGOTS!

Post Edited (Frohman) : 7/31/2010 3:53:07 AM GMT