From b2ae702c484b9fc665e49d3b6d9b57cb2a0588a4 Mon Sep 17 00:00:00 2001
From: Adam Greenwood-Byrne <adam@greenwoodbyrne.com>
Date: Tue, 11 Aug 2020 17:48:00 +0100
Subject: [PATCH] Notifications working for ATT characteristic

---
 part7-bluetooth/bt.c     |  8 ++++----
 part7-bluetooth/bt.h     |  2 +-
 part7-bluetooth/kernel.c | 13 +++++++------
 3 files changed, 12 insertions(+), 11 deletions(-)

diff --git a/part7-bluetooth/bt.c b/part7-bluetooth/bt.c
index acf7547..c91c854 100644
--- a/part7-bluetooth/bt.c
+++ b/part7-bluetooth/bt.c
@@ -194,18 +194,18 @@ void bt_getbdaddr(unsigned char *bdaddr) {
     for (int c=0;c<6;c++) bdaddr[c] = bt_waitReadByte();
 }
 
-void sendACLreadreq(unsigned int handle)
+void sendACLsubscribe(unsigned int handle)
 {
     bt_writeByte(HCI_ACL_PKT);
 
     bt_writeByte(lo(handle));
     bt_writeByte(hi(handle));
 
-    unsigned int length = 0x0007;
+    unsigned int length = 0x0009;
     bt_writeByte(lo(length));
     bt_writeByte(hi(length));
 
-    unsigned int data_length = 0x0003;
+    unsigned int data_length = 0x0005;
     bt_writeByte(lo(data_length));
     bt_writeByte(hi(data_length));
 
@@ -213,7 +213,7 @@ void sendACLreadreq(unsigned int handle)
     bt_writeByte(lo(channel));
     bt_writeByte(hi(channel));
 
-    unsigned char params[] = { 0x0a, 0x2a, 0x00 };
+    unsigned char params[] = { 0x12, 0x2b, 0x00, 0x01, 0x00 };
 
     unsigned int c=0;
     while (c++<data_length) bt_writeByte(params[c-1]);
diff --git a/part7-bluetooth/bt.h b/part7-bluetooth/bt.h
index e0c1c75..192fdb5 100644
--- a/part7-bluetooth/bt.h
+++ b/part7-bluetooth/bt.h
@@ -13,4 +13,4 @@ void stopScanning();
 void startActiveAdvertising();
 void connect(unsigned char *addr);
 void bt_flushrx();
-void sendACLreadreq(unsigned int handle);
+void sendACLsubscribe(unsigned int handle);
diff --git a/part7-bluetooth/kernel.c b/part7-bluetooth/kernel.c
index 32e297b..43d3ab5 100644
--- a/part7-bluetooth/kernel.c
+++ b/part7-bluetooth/kernel.c
@@ -1,6 +1,5 @@
 #include "io.h"
 #include "bt.h"
-#include "fb.h"
 
 #define memcmp         __builtin_memcmp
 
@@ -176,11 +175,13 @@ void acl_poll()
 
 	  length = data[0] | (data[1] << 8);
 
-	  unsigned int channel =  data[2] | (data[3] << 8);
-
+	  unsigned int channel = data[2] | (data[3] << 8);
 	  unsigned char opcode = data[4];
-	  if (opcode == 0x0b) {
-             for (int c=0;c<length-1;c++) uart_byte(data[5+c]);
+
+	  if (opcode == 0x1b) {
+             unsigned int from_handle = data[5] | (data[6] << 8);
+	     
+             for (int c=0;c<length-3;c++) uart_byte(data[7+c]);
 	     uart_writeText("\n");
 	  }
        }
@@ -222,7 +223,7 @@ void main()
     // Get the characteristic value
     uart_writeText("Sending read request: ");
     uart_hex(connection_handle); uart_writeText("\n");
-    sendACLreadreq(connection_handle);
+    sendACLsubscribe(connection_handle);
 
     // Into the main infinite loop
     uart_writeText("Waiting for input...\n");