I'm trying to interface the PIC to a PC through the USART.

I tried to set up the registers based on the datasheet. The TX pin
goes high, but when I try to transmit, it just stays high with no
signal. Any ideas what could be causing this?

Thanks,
Jason

My test code is:

include f877_4
include jlib

var volatile byte SPBRG at 0x99
var volatile byte TXSTA at 0x98
var volatile byte RCSTA at 0x18
var volatile byte TXREG at 0x19
var volatile byte RCREG at 0x1a
var volatile byte PIR1 at 0x0c

-- set USART up
pin_c6_direction = output -- transmit is an output
pin_c7_direction = input -- receive is an input
TXSTA = 0b_0010_0100 -- asynch, 8-bit, transmit enabled
RCSTA = 0b_1001_0000 -- asynch, no address detect, 8-bit

-- set for 300 baud
SPBRG = 207
BRGH = low

var bit LED is pin_b1
pin_b1_direction = output

forever loop
delay_100ms( 5 )
LED = high
TXREG = "H"
TXREG = "e"
TXREG = "l"
TXREG = "l"
TXREG = "o"
TXREG = " "
delay_100ms( 5 )
LED = low
end loop
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