Diff: PPP-Blinky/ppp-blinky.h

Revision:

153:7993def8663f

Parent:

152:025c73b6c0a9

Child:

154:18b2bd92f557

--- a/PPP-Blinky/ppp-blinky.h	Fri Sep 01 15:25:04 2017 +0000
+++ b/PPP-Blinky/ppp-blinky.h	Fri Sep 01 15:44:06 2017 +0000
@@ -6,11 +6,12 @@
 
 void initializePpp();
 int connectedPpp();
-void scanForConnectString();
+void waitForPcConnectString();
 void waitForPppFrame();
 void determinePacketType();
 
-typedef struct { // ff 03 00 21 
+/// structure of a PPP header
+typedef struct { // [ff 03 00 21]
     unsigned int pppAddress : 8,  // always 0xff
              pppControl : 8,  // always 03
              pppProtocol : 16; // 2100 for IP (byte reversed, should be 0021)
@@ -41,6 +42,7 @@
     unsigned int    dstAdr; // destination IP address
 } ipHeaderType;
 
+/// structure of TCP header when ip header is 20 bytes long
 typedef struct {
     ipHeaderType ip; // first part of TCP header is IP header
     unsigned int srcAdr : 16, // byte reversed
@@ -61,9 +63,10 @@
     unsigned int tcpOptions[10]; // 10 words of options possible
 } tcpHeaderType1;
 
+/// structure of TCP header when ip header is 24 bytes long
 typedef struct {
-    ipHeaderType ip;
-    unsigned int options; 
+    ipHeaderType ip; // first part of TCP header is IP header
+    unsigned int options; // extra 4 bytes in IP header
     unsigned int srcAdr : 16, // byte reversed
              dstAdr : 16; // byte reversed
     unsigned int seqTcp;