I am trying to get a PIC17c44 to echo characters to a PC through a =
serial port.  I *have* confirmed that the hardware around the pic is =
working properly.  I have noticed that when a character is typed in =
hyperterminal, the pic seems to receive only every other bit of the =
data, and then pads the remaining four bits (using 8 data bit, asynch =
mode) with 1's.  I suspect this is caused by the pic checking the values =
on the RX line too infrequently and then picking up stop bits (high) and =
filling the remaining 4 bits with '1's.  I am using d'32' in the spbrg =
and am able to send and receive characters to and from the pic, just not =
what I should be getting.

Example #1:

type 'a' 0x61 b'0110 0001' in hyperterm
recv  0xF4 in pic (output to a port) b'11110100' (the low nibble of this =
byte is everyother bit of the 'a'.
"echo" to PC
PC recvs '0' 0x30 -- don't know what is happening here.
(Example 1 occurs for all characters which have 0100 =3D to every other =
bit)

Example #2
type 'b' 0x62 b'0110 0010'
recv 0xF5 in pic '1111 0101'  (low nibble is every other bit of 'b')
echo to PC
PC recvs '6' 0x36 -- don't know what is happening here.
(Example #2 happens for all characters which have 0101 =3D to every =
other bit)

Is there some way to change the RCREG sampling timing, or am I on a wild =
goose chase?

Any help would be greatly appreciated,

Thanks,

Paul

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