634 Embedded Problems

WireNut

New member
Here's the background info:

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LCD Information
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634 Lcd
RS232 for communications
baud @9600
dip switches set to 9600

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Embedded System Info
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Using Oopic for embedded circuit
Serial communications w RS232 no flow control
baud set @ 9600

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Hyperterminal
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RS232 for communications
baud @9600
No flow control
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With the above in mind:

I am using the same cable for all of the following:

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Scenerio 1 - PC Running Hyperterminal connected to LCD
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Boot Screen comes up/off in 5 seconds
Typed characters appear as typed in hyperterminal

Everything works great :)

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Scenerio 2 - PC Running Hyperterminal connected to Oopic
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Oopic sends menu information to Hyperterminal
Hyperterminal recieves and displays correctly

Everything works great :)

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Scenerio 3 - LCD connected to Oopic
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Oopic sends menu information to LCD

No change in lcd

I can see the cursor so it isn't the contrast

Scenerio 1 verifies that the lcd receives and displays info sent from hyperterminal

Scenerio 2 verifies that the Oopic sends info and displays in Hyper Terminal

Hyper Terminal to LCD = Good
Oopic to Hyper Terminal= Good
Oopic to LCD = Bad(and Frustrated)

Any ideas on what else to try????:confused:

Note that the only change between scenerios is moving the serial cable from pc to Oopic, used same cable

Verified that all units work

Can't get Oopic to talk to LCD

Any help will be greatly appriciated
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WireNut

New member
After typing out the problems I was having it became almost obvious what my problem was.

The receive of the serial port from the embedded system(Oopic) was connected to the receive of the lcd 634.

Swapping the transmit and receive at the Oopic solved the communication problems.

Another problem that i encountered was that the control characters for the lcd, for example form feed is a \012.

In order for my Oopic to transmit this to the lcd it was necessary to send this. --- chr$(012)

chr$(012) essentially is the ascii 12 but without using that format the data never appeared on the lcd.
 
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