How to receive stream of bytes using PIC USART

[dhouston]

OK - it has only one stop bit. It appears that various manufacturers use their own protocol.

60 packets per second x 5 bytes per packet x 10 bits per byte = 3000 bits per second which, at 4800bps, means 30 (or fewer - depends on pace) idle bit-times between packets.

I would capture 10 bytes, scan them for the first initial byte (>127) and then look at the following 4 bytes for your data.

EDIT: 9 bytes would guarantee one complete packet.

[Ioannis]

Hmm, seems that is like the pdf I posted. Is it the same module?

Based on the infos and the idea of Dave's:

array    var   byte[9]
temp    var   byte
i          var   byte
j          var   byte

get_new_data:
SerIn2 PORTB.7,16572,[str array\9]
for i=0 to 8
    temp=array[i]
    if temp.7=1 then goto send_at_9600
next i
hserout ["Not found!",13,10]
goto get_new_data

for j=i to i+4
hserout [array[j]]
next j

goto get_new_data

end

Hope this will get you started. Don't forget the defines for the Hserout command to set it at 9600.

Ioannis

[dhouston]

You need only scan the first five bytes to find the start of a packet. And you can save one step on each loop.

for i=7 to 39 STEP 8
    if array[0].i=1 then goto send_at_9600
next i

[unifoxz]

Thanks for the suggestions, but the result I get is still not correct.

Have anyone tried to send an endless stream of bytes to PIC and then resend the stream back to PC? Will the input bytes same as the output bytes?

[Ioannis]

Please post you complete code as is now.

Of course the PIC will send the correct bytes as received, why shouldn't??

Ioannis