USART with INTERRUPTS

[crhomberg]

Yes, just a loopback

[skimask]

Yes, just a loopback

See post 6. Are you using a max232 or the resistors like in the manual?

AND WHICH VERSION OF PBP ARE YOU USING?

[crhomberg]

I tried the tester as below (cut & paste except the range) but just a a list of ascii garbage. I am monitoring using the microcode studeo serial communicator and have tried receiving at various speeds.
The output is via a 1K resistor.

Regards

Chris

´*********************************

@ device hs_OSC, wdt_on, pwrt_on, protect_off
define osc 20

DEFINE HSER_RCSTA 90h ' Enable serial port & continuous receive
DEFINE HSER_TXSTA 20h ' Enable transmit, BRGH = 0
DEFINE HSER_SPBRG 64 ' 2400 Baud @ 4MHz, 0.17%
DEFINE HSER_CLROERR 1 ' Clear overflow automatically

Pause 500

Start:
FOR SPBRG=15 to 100
HSEROUT ["SPBRG=",#SPBRG]
PAUSE 50
NEXT
stop 'put this in to do it only once
GOTO Start

[crhomberg]

By the way,

I am using PBP version 2.46

Regards

Chris

[Charles Linquis]

If you are using HSERIN/HSEROUT, you can't simply use a resistor. The data is inverted compared to what it needs to be in order to communicate with any normal serial device (such as a PC).

A MAX232 (or equivalent), not only changes the voltage swings and levels, it inverts the signals as well.

[crhomberg]

Thanks to both of you,

I have finally had success but I have to admit that the problem was me all the time and I only added the MAX232 at the end but still had problems.
All that was needed was a decoupling cap on the Max232.

I have to eat humble pie today!

Thanks all,

You have kept my sanity

Regards

Chris