我陷入了Digi Xbee ConnectPort X3和嵌入式主板之间的串行通信。 Digi Xbee是python代码。我正在以数据包的形式将digi的温度和光传感器值发送到电路板:
Sync | Low Byte | High Byte | Data | Checksum
设备接受。我单独测试了两个设备。他们工作得很好。我使用pyserial
从我的计算机向嵌入式主板发送数据,它可以完美地接收数据(大约30个数据)。然后我检查了Digi是否在COM端口使用我的电脑完美地发送数据。但是当我将Digi设备连接到电路板时,digi发送的数据非常少(1到3),即我可以将digi Xbee调试到一个扩展,我在发送数据后看到Digi Xbee的COM端口关闭。
我已经添加了Digi Xbee的部分源代码供您理解
open()
while True:
# Retrieve a sample reading from the LT
flushInput()
flushOutput()
io_sample = xbee.ddo_get_param(sensor_address, “is”)
light = parseIS(io_sample)["AI1"]
temp = parseIS(io_sample)["AI2"]
hum = parseIS(io_sample)["AI3"]
mVanalog = (float(temp) / 1023.0) * 1200.0
temp_C = (mVanalog – 500.0)/ 10.0 # – 4.0
lux = (float(light) / 1023.0) * 1200.0
print “hum:%f” %hum
sync=254
temp=round(temp_C,2)
light=round(lux,2)
no_temp = len(str(temp))
no_light = len(str(light))
total_length=no_temp+no_light+3+2
if total_length<256:
low_byte=total_length
high_byte=0
else:
low_byte=total_length%256
high_byte=high_byte/256
msg_id_low=0
msg_id_high=0
checksum=low_byte+high_byte+msg_id_low+msg_id_high+ord('#')+ord(':')+ord(',')
t=str(temp)
for c in t:
if c == '.':
checksum+=ord('.')
else:
checksum+=ord(c)
t=str(light)
for c in t:
if c == '.':
checksum+=ord('.')
else:
checksum+=ord(c)
checksum=256-(checksum%256)
if checksum == 256:
checksum=0
print "Checksum Value after applying mod operator:%d" %checksum
packet=str(chr(254))+str(chr(low_byte))+str(chr(high_byte))+str(chr(msg_id_low))+str(chr(msg_id_high))+str('#')+str(temp)+str(':')+str(light)+str(',')+str(chr(checksum))
print "packet:%s" %packet
bytes_written = write(packet)
print "bytes_written : %s value : %s" %(bytes_written,packet)
time.sleep(15)