Reading a Hex value from a Modem and showing it as Decimal..

[Tom Gonser]

I have a simple gosub which asks the modem for a value, and this value is returned as a HEX value. Example in Hyperterminal:

"+++" ' sent to modem to enter AT command
OK ' modem responds OK
ATRS ' sent to modem - what is your RS value?
33 ' modem response (actually it sends back HEX values)
ATCN ' sent to modem to exit AT command

The value of RS will typically range from 6 – 54 (0x06 – 0x36 hex). This above answer of '33' equates to a decimal value of 51.

I want to read this RS on my 16F88, and display RS as a DECIMAL value and can't seem to get the right numbers to come out.. Here is the code:

dis4:
' third pass - RSSI
' Send command to radio and read RS value back

Serout2 Cpinout,84,["+++"]
Serin2 Cpinin,84,1000,noradio,[Wait ("K")]
Serout2 Cpinout,84,["ATRS",10,13]
Serin2 Cpinin,84,1000,noradio,[STR RSSI\2]
serout2 cpinout,84,["ATCN",10,13]
SSD1=RSSI[1]
SSD2=RSSI[2]
RSSIval=(ssd2*16)+ssd1 ' convert to dec
serout2 Apinout, 16468, [I,CLR]
serout2 Apinout, 16468, [I,L1_C1]
serout2 Apinout, 16468, ["RSSI: ",#RSSIval Dig 2, #RSSIval Dig 1]
pause 1000
Return

Anyone have any ideas? I am seeing '03' or '04' when it should be sending '51' or some number in that range...

NAKKK!!

[Ingvar]

Modems usually respond very fast to commands, that means that your pic may not be ready to recieve when the modem sends. You may for this reason miss the first character in each transmission. To cure this problem you can try running at 20MHz , if that's not enough you need to use the hardware USART. The 16F88 should have one ..... i think.