From: Erik Andresen <erik@vontaene.de>
Date: Sat, 21 Nov 2020 16:42:57 +0000 (+0100)
Subject: bus_pirate: add i2c ping
X-Git-Url: https://defiant.homedns.org/gitweb/?a=commitdiff_plain;h=580beb73ab16024ddfab56bc26ffa261c1790906;p=pyshared.git

bus_pirate: add i2c ping
---

diff --git a/bus_pirate.py b/bus_pirate.py
index d7c8eaf..02f3fb8 100644
--- a/bus_pirate.py
+++ b/bus_pirate.py
@@ -158,6 +158,15 @@ class BP:
 		if ord(ret) != 0x1:
 			raise Exception()
 
+	def i2c_ping(self, addr):
+		# 1. Write
+		# command (1) | number of write bytes (2) | number of read bytes (2) | bytes to write (0..)
+		msg = struct.pack(">BHHB", 0x08, 1, 0, addr)
+		ret = self.command(msg, 1)
+
+		if ord(ret[0]) != 0x1:
+			raise Exception("I2C ping failed")
+
 	def i2c_write(self, addr, reg, s):
 		# 1. Write
 		# command (1) | number of write bytes (2) | number of read bytes (2) | bytes to write (0..)
@@ -169,7 +178,8 @@ class BP:
 
 	def i2c_read(self, addr, reg, num_read):
 		# set reg
-		self.i2c_write(addr, reg, "")
+		if reg != None:
+			self.i2c_write(addr, reg, "")
 
 		# command (1) | number of write bytes (2) | number of read bytes (2) | bytes to write (0..)
 		msg = struct.pack(">BHHB", 0x08, 1, num_read, addr | 0x1)