Page 302 - Making PIC Microcontroller Instruments and Controllers

3O4 LOGGING DATA FFOM A SOIAR COLLECIOR

1. LAB-X1 board
2. A clock chipr NJU 6355
3. A smalllan ihat runs al 120 volls
4. Glass or plasiic io fit
sensof
5. One LM34 temperature
6. One old lBll-PC, working
7. One hafd d ve with 10 l\,lB ol memory lree
8. one serialcable ior CO[,41
sheet ol 1- nch Slyroloam
9. One 2-teel-by-8-leei
10. Half a sheel of lr-inch exterior grade plywood
11. Sorne 1-inch brads
12. Some wood g ue
13. The usual odds and ends

Microcontroller Hardware

Sinccit would be amajorexpensc aDd effo|t fof cach studenllo design rnd build a con-
trcllcr for this pfojcct. and since $c rh rdy halc a LAB-XI available to us. we \\'ill
use thc LAts-Xl as thc contfollet lb lhe pfoject. This will limit $hat we can do a bit
but sincc ihe mair function of the ercrcise is daia collcction, this will not distracl iionr
the ej(pericnce $,e are sccking.
need 1() make the lbllowing changcs/modificadons
In order to use the LAB X l. .|l'e
to the bo:rd:

1. Add a clock chD in U6.
2. Add a crysul for lhe clock chip rt J5.
3, Add heaclers to the LAB-XI alPl. P2. P3, and P4 so we can connect to lhc MCU as

The diagran in Figure 22.2 refiects thc modifications lhat have to bc made Of partic-
ulaf irterell is the fact thil thcre arc tluee potcntiometers the board that can interlcrc
on
to lbr rcading any
with our using ihe thfee lincs thatthey areconnected jinuts Howevfl.
the potendonreteN can bc used to modiii variables we arc using (for exa ple, the lcln
peralurc al which we nnr1 o the fan), ard wc can siill Lrsc the lines for VO if we sel the
posjtions.Ifwe do !hat, the irputs \l'ill be ablc
potenriomelcrs approprialc intermediate
to
lo olerride the intcmrediaie seltings and we can rcad the inPut. (The program as $'ritten
docs rot use ihese pots. but you should be arvtre that this car be done )