Serial Configuration

   Though we recommend using TclTerm to talk to the ARMstamp, here are settings for other terminal programs. 

Baudrate

   115.2 Kbaud, 8 bit, No Parity, 1 stop bit

End of Line

   expects a LF (line feed),  

   CR is currently ignored.

Voltage Levels

   /SOUT, /SIN and ATN (pins 1,2,3) will accept either TTL or RS-232 levels. ATN when high resets the ARMstamp, and ATN should not be allowed to float. It should either be connected directly to DTR, or some TTL signal that is LOW or Ground. The /SOUT driver relies on either /SIN or ATN being low to generate the low going voltage. This allows for full-duplex serial operation.

Handshaking

   XON/XOFF (software handshaking) is used only during programming of the Flash.  When downloading a large program, a pause is required when the current amount of code in the buffer exceeds 8k (about 5-600 lines).  That buffer will be written to Flash which takes about 1 second.  A total of 40K is available to the user for code, constant strings and DATA.

Break operation or STOP

   If the user code is running, it can be stopped by a RESET condition.  This will normally restart the user code, but there is a short window (200 msec) where the ARMstamp will wait to see if there is input on the serial debug port.  If the character received on the serial port is ESCAPE (27) or CTL-C (3)  then the user program is prevented from running and the ARMstamp is ready to be reprogrammed.  Or the user can restart the program by typing RUN or using the RUN button in TclTerm.

Program Running Signaling (ver 6.11 and after)

  When the user code starts running, an SOH (\1) character is sent, and when the user code stops an EOTX (\4) is sent. This was added for the ARMmite, as TclTerm needs to know when the user code is running.  ARMstamp versions starting with 6.11 also support this.

When TclTerm appears to be deaf

   There are cases where the USB driver and TclTerm get out of sync.  This includes when the board is disconnected from the USB port, and sometimes when the serial configuration is changed.  In these cases it may be necessary to exit TclTerm and then restart it, and in some cases reboot the system.

TclTerm configuration settings

   The configuration of TclTerm is saved in a file TclTerm.ini.  It is written when either it does not exist (when first installed) or when the configuration is changed by the user.  This file is a Tcl source which may be edited by the user.  If it becomes corrupt, delete the file and the default configuration will be restored.