Hi,All: In my application I'm using a ARM7 (from NXP) with a serial Interface (RS232) to connect with a CDMA modem. After dial the number and received "CONNECT",beginning to exchange LCP data,but In the data of the ARM7 losesd the "FF 03",what's the reason?
Now it entries IPCP REQ: ARM: 7E FF 03 80 21 10 01 01 00 1A 03 06 00 00 00 00 //local IP 90 8B 7E but do not receive IPCP ACK.
"How to do not lose 'FF 03' "
"FF 03" are the HDLC address and control bytes (i.e., the first two bytes within the frame encapsulated between the [7E] flags). If your software is not properly tracking the framing flags, you might not recognize the address and control bytes in their proper context. Some implementations allow the first flag to be omitted when transmitting back-to-back frames. Are you accounting for that?
Can I send my program to your email?
thank you! I do not understand what's you mean? How to do not lose "FF 03"
Seriously now, your software is not tracking PPP framing properly.
The ARM7 has to be explicitly programmed to not losesd the "FF 03". Did you skip that step?
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