Hi all - I have some work to finish a 16F temperature logging project for=20
someone (paid for a working version within the next 3 days)

It is using a PIC16F877, 4-line LCD with 4 buttons attached to the DB4-7=20
lines, 4 Maxim DS18B20 temp sensors, a couple of 32KB I2C eeproms, a MOSFET=
=20
to switch the LCD off when the PIC sleeps between readings (every hour for=
=20
at least 10 weeks) and a Maxim DS1307 RTC to timestamp and trigger the=20
interrupt to wake up and take reading.
All is working reasonably for and has been for a while on a breadboard, but=
=20
the chap I'm doing it for has it's own board that has been fraught with=20
problems from the start (I offered to do the whole thing myself and send it=
=20
fully working to him, but he wants to do it this way, which means I have to=
=20
write code, then send it to him and debug remotely...)

To get to the point - we are using a Max232 to Hyperterminal to upload the=
=20
data to the PC. I was using the PicKit2 Uart tool with no problems at all,=
=20
but with Hyperterminal things behave strangely - it gets to the end of the=
=20
readings (say 100 for now) then the cursor files down the screen with=20
newlines and cannot be stopped, like it loses itself. At this point I get a=
=20
"serial not present" message on the LCD (I show a message on=20
connect/disconnect)
The odd things the PIC, carries on with no problems - it does not hang, and=
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will carry on taking readings if they are activated. Putting a scope probe=
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on the Tx output pin of the Max232 though appears to show data still being=
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sent, even though the PIC is NOT actually sending anything and proceeding=20
normally??
I am not very experienced with Hyperterminal, or indeed RS232(before my tim=
e=20
really - I have always used USB) but as this is not my project I have no=20
choice. I know there is better software available but would like to know=20
what is going on with Hyperterminal, just in case he insists on using it.
I am thinking it may be something to do with not using a null modem cable?=
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the PC thinks it's talking to a modem and expects some handshake at the end=
?
Any suggestions as to what is causing this would be great - by the way, I=20
can send one or two lines okay to the PC, it seems to be just when a lot of=
=20
data is sent that it does this.
Any ideas?
=20


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