Alt-BEAM Archive

Message #07641



To: "'Jason -'" evenflow88@hotmail.com
From: Wilf Rigter Wilf.Rigter@powertech.bc.ca
Date: Sat, 13 Nov 1999 09:36:08 -0800
Subject: [alt-beam] Re: solar smart head(jim and Wilf)


Hi Jason,

Well it looks like our friend James V. Mullins (Vernon is his middle name)
won't reveal all his secrets but me thinks Jim does not follow his own
advice and misses an opportunity by not using the chloroplast SE.

Anyway diagnosing CMOS trouble: in this example we test a 74HC/AC240
separate from the application circuit

1. check the chip by itself, preferably on a solderless plug-in proto board.
Prepare all connections before applying power.
2. connect the power pins of the 74HC240 pin 10=0V and pin 20=+5V (3x1.5V
batteries are OK)
3. connect a 1k-1M resistor from +5V to each 240 input pins
1,2,4,6,8,11,13,15,17and 19
4. make a logic probe by connecting a LED with a series 100 -1000ohm
resistor to 0V and a long jumper wire to 5V.
5. turn on the power. The LED should light. If not, turn LED around.
6. disconnect the long jumper wire that connects LED from +5V line: the LED
goes dark.
7. tap +5V with the jumper and the LED should flash
8. next tap all 240 output pins (3,5,7,9,12,14,16,18) with the jumper: the
LED must not light.
9. connect a jumper from pin 1 to 0V and tap LED jumper to 12,14,16,18: the
LED flashes and tap 3,5,7,9: the LED stays dark
10. connect a jumper from pin 19 to 0V and tap LED jumper to output pin
3,5,7,9: the LED flashes
11. connect LED jumper to output pin 18 and another jumper to 0V and tap
input pin 2: LED should flash
12. repeat step 11 for all pairs of output and input pins ie 16/4, 14/6,
12/8, 9/11, 7/13, 5/15, 3/17
13. connect a small motor from pin 7 to pin 9
14. connect a jumper from 0V to pin 11: motor turns one direction: if not go
to step 21
15. connect another jumper from 0V to pin 13: motor stops.
16. remove jumper from pin 11: motor turns in the other direction:if not go
to step 21
17. remove jumper from pin 19: motor stops If parallel outputs as per step
21: the motor slows down. Hey! SPEED CONTROL!.
18. If all steps were successful the chip is probably good.
19. now add other components as per design tutorial: checking the result of
each step until you have checked the entire circuit
20. You have checked the chip and the circuit so you're done or perhaps now
you are ready to hardwire the circuit.
21. if the motor does not turn or turns too slow in step 14 and 16, connect
inputs and outputs in parallel to increase current.
22. connect a jumper from pin 7 to 14, from pin 9 to 12, from pin 6 to 13
and from pin 8 to 11.
23 repeat steps 14 -20

I hope this will help you debug the CMOS chip.

BTW unlike walkers, no motor feedback is required or even desirable for a
head application.

regards

Wilf Rigter mailto:wilf.rigter@powertech.bc.ca
tel: (604)590-7493
fax: (604)590-3411

> -----Original Message-----
> From: Jason - [SMTP:evenflow88@hotmail.com]
> Sent: Friday, November 12, 1999 9:15 PM
> To: beam@sgiblab.sgi.com
> Subject: RE: solar smart head(jim and Wilf)
>
>
>
> Hie everyone esspecially jim and wilf..I would really like to know what
> jim
> vernon uses for his power smart head configuration..it seemed to have so
> many resistor than usual...and wilf could u guide me step by step how i
> could test whether a CMOS chip is working or not and how and why do i
> need
> to know the feedback of the gearmotor from the PSH circuit..thanks a lot
>
> p/s:what SE did u use for the head jim and whats the cap value?
>
> jason
>
> ______________________________________________________
>


7642 Sat, 13 Nov 1999 12:53:30 -0800 [alt-beam] Re: solar smart head(jim and Wilf) "Rik" Jim - did you make the pcb for that head?

where can one find a parts list and scematic for that bad boy!! ???

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