CQ_I2C_book
I2C-bus master selector with interrupt logic and reset
Dependencies: mbed
Revision 0:62f897b8acfa, committed 2015-02-04
- Comitter:
- wataaki
- Date:
- Wed Feb 04 06:01:04 2015 +0000
- Commit message:
- initial version
Changed in this revision
| PCA9541A.cpp | Show annotated file Show diff for this revision Revisions of this file |
| mbed.bld | Show annotated file Show diff for this revision Revisions of this file |
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/PCA9541A.cpp Wed Feb 04 06:01:04 2015 +0000
@@ -0,0 +1,68 @@
+#include "mbed.h"
+
+I2C i2c(p28,p27); // sda, scl
+Serial pc(USBTX, USBRX); // tx, rx
+char cmd[32];
+int i, j, k;
+int sw;
+
+void set_ch(char sel)
+{ // PCA9541のサンプル
+ // MST_0側の自分にスレーブ側の制御権を得る場合
+ cmd[0] = 1; // PCA9541 コマンドコード Cont Reg
+ i2c.write( 0xe2, cmd, 1); // Cont Regを指定
+ i2c.read( 0xe2, cmd, 1); // Cont Regを読込み
+ wait(0.1); // 0.1s待つ
+ switch(cmd[0] & 0xf)
+ {
+ case 0: // bus off, has control
+ case 1: // bus off, no control
+ case 5: // bus on, no control
+ cmd[0] = 1; // PCA9541 コマンドコード Cont Reg
+ cmd[1] = 4; // bus on, has control
+ i2c.write( 0xe2, cmd, 2); // Cont Regにcmd[1]を書込み
+ i2c.read( 0xe2, cmd, 1); // Cont Regを読込み
+ break;
+ case 2: // bus off, no control
+ case 3: // bus off, has control
+ case 6: // bus on, no control
+ cmd[0] = 1; // PCA9541 コマンドコード Cont Reg
+ cmd[1] = 5; // bus on, has control
+ i2c.write( 0xe2, cmd, 2); // Cont Regにcmd[1]を書込み
+ i2c.read( 0xe2, cmd, 1); // Cont Regを読込み
+ break;
+ case 9: // bus on, no control
+ case 0xc: // bus on, no control
+ case 0xd: // bus off, no control
+ cmd[0] = 1; // PCA9541 コマンドコード Cont Reg
+ cmd[1] = 0; // bus on, has control
+ i2c.write( 0xe2, cmd, 2); // Cont Regにcmd[1]を書込み
+ i2c.read( 0xe2, cmd, 1); // Cont Regを読込み
+ break;
+ case 0xa: // bus on, no control
+ case 0xe: // bus off, no control
+ case 0xf: // bus on, has control
+ cmd[0] = 1; // PCA9541 コマンドコード Cont Reg
+ cmd[1] = 1; // bus on, has control
+ i2c.write( 0xe2, cmd, 2); // Cont Regにcmd[1]を書込み
+ i2c.read( 0xe2, cmd, 1); // Cont Regを読込み
+ break;
+ default:
+ break;
+ }
+
+ cmd[0] = sel; // PCA9546 Cont Reg sel channel enabled
+ i2c.write( 0xe8, cmd, 1); // Send command string
+}
+
+int main ()
+{
+ i2c.frequency(100000);
+ pc.printf("PCA9541A Sample Program\r\n");
+
+ set_ch(1); // PCA9541Aによりマスターを選択後
+ // PCA9546によりchｎに接続
+
+ // PCA9541A
+ while(1);
+}
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/mbed.bld Wed Feb 04 06:01:04 2015 +0000 @@ -0,0 +1,1 @@ +http://mbed.org/users/mbed_official/code/mbed/builds/4fc01daae5a5 \ No newline at end of file