# HG changeset patch
# User Paul Boddie <paul@boddie.org.uk>
# Date 1609973671 -3600
# Node ID 84945015fb9c287520e6ba1bdb6c9ce4bf349123
# Parent  99302c954b99fa520e9e944084502406e5c4e584
Added testing of the voltage level and charging status, and of powering down.

diff -r 99302c954b99 -r 84945015fb9c pkg/landfall-examples/letux400_i2c/letux400_i2c.cc
--- a/pkg/landfall-examples/letux400_i2c/letux400_i2c.cc	Wed Jan 06 00:46:11 2021 +0100
+++ b/pkg/landfall-examples/letux400_i2c/letux400_i2c.cc	Wed Jan 06 23:54:31 2021 +0100
@@ -210,7 +210,7 @@
 
   printf("Written: %d\n", nwritten);
 
-  do
+  for (int i = 0; i < 3; i++)
   {
     /* Issue selection of device register 0. */
 
@@ -232,6 +232,24 @@
 
     rtc_datetime(buf);
 
+    /* Read from the power controller at 0x28. */
+
+    buf[0] = 0xdb;
+    nwritten = jz4730_i2c_write(i2c0, 0x28, buf, 1);
+    printf("Written: %d\n", nwritten);
+    nread = jz4730_i2c_read(i2c0, 0x28, buf, 1);
+    printf("Read: %d\n", nread);
+
+    printf("Voltage level: %1.3f\n", buf[0] * 36235 / 1000000.0);
+
+    buf[0] = 0xd9;
+    nwritten = jz4730_i2c_write(i2c0, 0x28, buf, 1);
+    printf("Written: %d\n", nwritten);
+    nread = jz4730_i2c_read(i2c0, 0x28, buf, 1);
+    printf("Read: %d\n", nread);
+
+    printf("Charger connected: %s\n", buf[0] & 1 ? "yes" : "no");
+
     /* Scan the bus. */
 
     printf("Scan I2C0...\n");
@@ -239,7 +257,12 @@
 
     sleep(5);
   }
-  while(1);
+
+  /* Issue a shutdown request. */
+
+  buf[0] = 0xd8; buf[1] = 1;
+  nwritten = jz4730_i2c_write(i2c0, 0x28, buf, 2);
+  printf("Written: %d\n", nwritten);
 
   /* Detach from the interrupt. */