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How does RealTerm send numbers? For some reason, when I enter a number under the "Send" tab to be sent over the serial line in RealTerm, it works, but inputting the same commands in PuTTY through the command line does not work. What is the reason for this?

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up vote 1 down vote accepted

If you're using the Send Numbers button after typing a decimal number (or several or they could be hexadecimal, etc.), it's sending the character that corresponds to that code. In PuTTY, if you want to send an ASCII 65 (decimal) then you'd type an "A". If you want to send an ASCII 11 (decimal - Vertical Tab) you could press Ctrl-K or hold down the Alt key and type 11 on the numeric keypad.

Without knowing what you're communicating with, what it expects for input, whether you have PuTTY configured properly, etc., that's the best I can do.

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Thanks for the answer. I am trying to communicate with an iRobot series 500 Roomba. I am not quite sure what it expects and trying to figure that out. The iRobot SCI documentation lists opcodes which can be sent to the Roomba to control it. Right now, I am trying to send the two opcodes 128 and 133 to the Roomba. In Realterm, all I have done is go to the "Send Numbers" button. In PuTTY, I have tried communicating with the serial port using the same baud & other config + forcing local echo and line editing on, to no avail. Can you help? – tushark Feb 15 '11 at 5:42
@tushark: I'm not familiar with communicating with or controlling a Roomba. Are those opcodes decimal byte values or ASCII digit characters? It seems like they are the former. If you hold down Alt and press 128 on the numeric keypad and release Alt do you get any response? Is the Roomba showing any startup output (copyright message, prompt string, etc.) when you use PuTTY? Since RealTerm works, why not continue using it? – Dennis Williamson Feb 15 '11 at 6:05
@tushark: Now that I've had a chance to glance at the docs, I see that they are byte values so there's a good chance that the Alt key technique will work. By the way, I don't see an opcode 133 documented. – Dennis Williamson Feb 15 '11 at 6:21
@dennis-williamson I am trying to figure out the data type that I need to send to the Roomba and don't have a numeric keypad. I was using PuTTY / RealTerm to debug and need to figure out how to send the opcodes because I'm writing a program in PHP for the Roomba. Someone wrote a PHP serial class, so I can communicate with the Roomba, but the Roomba doesn't seem to be accepting any of my commands. StackOverflow question – tushark Feb 15 '11 at 6:22
@dennis-williamson Thanks for looking at the docs. Is there another method which doesn't use a numeric keypad? The 133 opcode is for powering the Roomba on and off. Thanks for the help once again! – tushark Feb 15 '11 at 6:24

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