Just to clearify what I have done, and never received an error :

     PIC   = 16C73
     BRGH  = 1
     SPBRG = 12-dec,  claculated : 12,02083333333-dec
     TXSTA : TX9  = 0
             TXEN = 1
             SYNC = 0
             BRGH = 1
     RCSTA : SPEN = 1
             RX9  = 0
             CREN = 1
     OSC   : 4MHz (XT)
     Transmitting computer :  19200 baud


     I was told that 16C73A did NOT have this bug...


     -Dag S



_______________________________ Svarseparator __________________________________
Emne: Re[3]: BRGH problem in 16C73,74
Opphavsperson:  Rodger Richey <Rodger.Richey@Microchip.COM> ved
Internet_Exchange
Dato:    21.11.96 07:57


     The errata involving BRGH=1 for the USART is present on all midrange
     microcontrollers with the USART module including the newer 'A'
     devices.

     This errata only affects the reciever of the USART, the transmitter
     remains unaffected.  We have found that some applications do not
     experience the errata.  It seems to be dependent on the oscillator
     frequency of the receiver, the baud rate, and the baud rate error of
     the transmitter.  The type of errors you would see are either framing
     errors or the data will simply be wrong.

     We have not been able to precisly define which combinations of osc.
     frequency and baud rate that do not produce errors, therefore we have
     suggested in the errata to not use BRGH = 1.

     Regards,

     Rodger Richey
     Sr. Applications Engineer
     Microchip Technology Incorporated


______________________________ Reply Separator _________________________________
Subject: Re[2]: BRGH problem in 16C73,74
Author:  Dag Bakken <Dag.Bakken@Microchip.COM> at Internet_Exchange
Date:    11/19/96 8:38 AM


> I understand that there is a problem in the silicon of the 16C73 and 16C74
> which means that you should never use BRGH=1 in the serial port.

That is correct


> Could anyone confirm that and advise if this problem is resolved in the 16C74A

It is fixed in the A version


> Anybody know what the problem does?

You may get errors in your transmission.  I've heard several different
error-rates;  from one error each 30 byte to one error each 100 byte.  I'm using
this mode myself in a project, and I have never gotten any errors...


-Dag S