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Step 7Prep for Using "spy-by-wire"
Once you have your panel meters with their new scales, you are ready to tune the calibration arrays for m_cal and h_cal in the C code.
There are several ways that you can proceed. One way is to fabricate the circuit on the breadboard and move the chip to the Launchpad each repetition of adjusting the array. The other way is to keep the chip in the Launchpad and isolate the prototyping portion of the board. This is done by removing the 5 jumpers from terminal block J3 and supplying 2.5V to the external power terminal block J6. When you want to program the chip you have to restore the jumpers and remove the external power supply. If you use this second method you have to hookup the meters and the buttons.
There is a third way, using the "spy-by-wire" interface. In this method when we build our project breadboard, we include some test points. The test points allow us to connect between the project breadboard and the Launchpad. We can program our microcontroller without ever removing it from the project board. The Launchpad is used simply as a programmer. This is the method that I recommend you use.
Adding the Test Points:
There are 4 test points that need to be added.
1. Vcc (IC pin 1)
2. Gnd (IC pin 14)
3. Test (IC pin 11)
4. RST (IC pin 10)
The simplest way to add a test point is to make a little U of wire and attach it at the desired location. See the pictures below.
There are several ways that you can proceed. One way is to fabricate the circuit on the breadboard and move the chip to the Launchpad each repetition of adjusting the array. The other way is to keep the chip in the Launchpad and isolate the prototyping portion of the board. This is done by removing the 5 jumpers from terminal block J3 and supplying 2.5V to the external power terminal block J6. When you want to program the chip you have to restore the jumpers and remove the external power supply. If you use this second method you have to hookup the meters and the buttons.
There is a third way, using the "spy-by-wire" interface. In this method when we build our project breadboard, we include some test points. The test points allow us to connect between the project breadboard and the Launchpad. We can program our microcontroller without ever removing it from the project board. The Launchpad is used simply as a programmer. This is the method that I recommend you use.
Adding the Test Points:
There are 4 test points that need to be added.
1. Vcc (IC pin 1)
2. Gnd (IC pin 14)
3. Test (IC pin 11)
4. RST (IC pin 10)
The simplest way to add a test point is to make a little U of wire and attach it at the desired location. See the pictures below.
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