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This example application demonstrates
use of the Serial Control Protocol (SCP) in firmware version 5.0.1
on an OOPicII+™ controller. It becomes accessible by using the
DS-IM RS232 Interface Module. The module allows commands to be sent
from an RS232 device (in this application a desktop PC), which can
then control the program flow of the connected OOPicII+ using SCP.
Connections
Using a 40 pin-40 pin IDC ribbon cable (part of the 2 module fixing
kit), connect the OOPicII+ 40 pin header to the outer most 40 pin
header on the DS-IM. The inner 40-pin header is used for IO connections
and is connected to the other 40-pin header.
The LED’s will be connected to the inner 40-pin header on the
DS-IM as follows:
The leg that is closest to the flat edge of the LED is connected to
Gnd.
The positive leg is connected to the designated pin on DS-IM via a
1K resistor. This resistor is needed other wise the LED will blow.
Red LED - Flat Edge Leg to Gnd - Positive Leg to 1K resistor
to Pin 20
Yellow LED - Flat Edge Leg to Gnd - Positive Leg to 1K resistor
to Pin 17
Green LED - Flat Edge Leg to Gnd - Positive Leg to 1K resistor
to Pin 19
The DS-IM can be mounted above the OOPicII+ using the spacers in the
2 module fixing kit.
The serial cable is connected to the DS-IM board via a female to male
gender changer (the DS-IM has a DB9F connector). The other end is
connected to a spare serial comm. port.
Download the Program
Download the program as normal from the OOPic compiler (Version 5.0.1).
Ensure the target device is set to OOPic Firmware Version B.2.x+.
Tools >Target Device > OOPic Firmware Version B.2.x+
Check that the programming cable is configured correctly.
Tools >Cable Configuration
The OOPicII+ can be programmed via the DS-IM using the serial comm.
port. In the Cable configuration window, select the comm. port you
are connected to and press Find Serial Cable. When found, press
ok. If no serial cable is found, make sure the DS-IM and OOPicII+
are powered up and try again. If it still cannot find it, double-check
what comm. port you are connected to.
When all the above is set, press F5 (compile and download). You will
be prompted to save the program if not already saved.
The three LED’s will be lit, but will be dimmer than usual. This
is because the LED’s are turning on and off very fast, so it
seems that they are on, even though this is not the case. We will
see the true pattern of LED lighting when we invoke the single step
command.
Serial Control Protocol (SCP)
The full set of SCP commands can be viewed at www.oopic.com. In this
application, we are demonstrating the use of Single Stepping.
*The Single Step command puts the OOPic's application program into
single-step mode. In firmware version B.2.0, the Step property was
added to the OOPic object.
*When the Step property is set to 1, the OOPic's Paused property will
be set to 1 after each OOPic instruction executes, thereby giving
the user the ability to single step through the program. The Start
Single Step command "P" set the Step property to
1 and also clears the Paused property to 0 so that a single instruction
gets executed. Issuing the Start Single Step command "P"
repeatedly, will execute one instruction per issue. The Stop Single
Step command "O" exits the single step mode by clearing
both the Step and the Paused property which results in the program
resuming.
Example: To single step through the program,
Send "\0V", Receive "v"
Send "0J", Receive "j"
Send "P" Receive "p"
(Turn on single step and execute one instruction)
Send "P", Receive "P" (execute one
instruction)
Send "P", Receive "P" (execute one
instruction)
Send "P", Receive "P" (execute one
instruction)
Send "P", Receive "P" (execute one
instruction)
Send "0", Receive "o" (Turn off
single step and resume program)
Note that the Step and Paused properties are also available
to the OOPic's application program. This gives the program the ability
to stop at a pre-programmed place and then wait for SCP to instruct
it to resume.
The above serial instructions can be sent using a hyper terminal (download
com 1 hyper terminal here). Type the characters above (no
need to press enter after each character) into the terminals window.
Responses will be displayed straight after a command has been sent.
When you send “P”, the OOPic will step through its
program. By doing this, the three LED’s will step through a traffic
light sequence. This demonstrates that the OOPic is being walked through
each line and command.
To return back to autonomous mode, the command “O”
is sent. The LED’s will all come on again.
*Taken from the OOPic Programmers Guide, Chapter 16, Serial Control
Protocol (SCP).
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