继电器常识:
继电器有三个接线柱:常开NO),常闭NC),接地C)
如果连接的时间长,偶尔需要断电, 那么接NC 和 C, 这样继电器set on 时为断电。除此之外,继电器还可以控制按键,以及长按。
继电器接通时,该继电器的灯会亮。ZZR08有8个继电器,以一个字节表示其整体状态,以每位的位高(bit high)代表对应继电器的状态。例如:第一个继电器set on 时为00000001,set off 时该位为0;第二个set on 时为000000102), set off 时该位为0。以此类推.
怎样使用继电器:
1. Command “ls /dev/tty*”, you can find like this
/dev/ttyRelayCard
在接入继电器之前运行“ls /dev/tty*”, 接入之后再运行一次,多出来的就是继电器的标识。
2. Check the file /etc/udev/rules.d/ACS.rules. In this file, there have a code like
this:
SUBSYSTEMS=="usb", ATTRS{idVendor}=="10c4", ATTRS{idProduct}=="ea60", SYMLINK+="ttyRelayCard", MODE="0666", OWNER="buildbot"
If there don’t have this code, please add it by manual. And then re-plugin the
relay card’s USB cable.
查看是否存在/etc/udev/rules.d/ACS.rules,如果不存在,则建立文件:touch ACS.rules,文件内容如上。
3. 查看权限:ls -l /dev/ttyRelayCard, 结果crw-rw—- 1 root dialout.
可以更改继电器权限:chmod a+rw /dev/ttyRelayCard. 这样坏处是,每次插拔继电器都要更改。
继电器的user是root, group是dialout。可以使当前用户从属于dialout用户组。查看user的用户组:groups user。更改user的附属用户组list: sudo usermod -G dialout,adm,…
4. python script
import serial import sys, time ''' ser = serial.Serial port=None, # number of device, numbering starts at # zero. if everything fails, the user # can specify a device string, note # that this isn't portable anymore # if no port is specified an unconfigured # an closed serial port object is created baudrate=9600, # baud rate bytesize=EIGHTBITS, # number of databits parity=PARITY_NONE, # enable parity checking stopbits=STOPBITS_ONE, # number of stopbits timeout=None, # set a timeout value, None for waiting forever xonxoff=0, # enable software flow control rtscts=0, # enable RTS/CTS flow control interCharTimeout=None # Inter-character timeout, None to disable ) ''' device = sys.argv[1] # /dev/ttyRelayCard ser = serial.Serialdevice, 19200, serial.EIGHTBITS, serial.PARITY_NONE, serial.STOPBITS_TWO, None) W = 0.05 def get_version): cmd = 90 print "get the relay software version" ser.writechrcmd)) time.sleepW) a = ser.read1) print orda) b = ser.read1) print ordb) time.sleep1) def set_relay_oni): ''' relay No is from 1 to 8''' cmd = 100 + i print "set relay %d on "%i) ser.writechrcmd)) time.sleepW) ser.writechr91)) # get relay states a = ser.read1) print orda) time.sleepW) def set_relay_offi): ''' relay No is from 1 to 8''' cmd = 110 + i print "set relay %d off"%i) ser.writechrcmd)) time.sleepW) ser.writechr91)) a = ser.read1) print orda) time.sleepW) set_relay_off1) # set_relay_on1)
newer edition:
import serial import sys, time ''' base API of controlling Relay. ''' class RelayControlobject): def __init__self, relay_id='/dev/ttyACM0', interval=0.05): self.relay_id = relay_id self.interval = interval self.handler = serial.Serialrelay_id, 19200, serial.EIGHTBITS, serial.PARITY_NONE, serial.STOPBITS_TWO, None) def get_versionself, cmd=90): print "get the relay software version" self.handler.writechrcmd)) time.sleepself.interval) a = self.handler.read1) print orda) b = self.handler.read1) print ordb) time.sleep1) def get_relay_statusself, cmd=91): self.handler.writechrcmd)) a = self.handler.read1) print orda) time.sleepself.interval) return orda) def set_relay_onself, relay_no): ''' relay No is from 1 to 8''' cmd = 100 + relay_no print "set relay %d on "%relay_no) self.handler.writechrcmd)) time.sleepself.interval) self.get_relay_status) def set_relay_offself, relay_no): ''' relay No is from 1 to 8''' cmd = 110 + relay_no print "set relay %d off"%relay_no) self.handler.writechrcmd)) time.sleepself.interval) self.get_relay_status) def set_all_relay_onself, cmd=100): print "set all relays on " self.handler.writechrcmd)) time.sleepself.interval) self.get_relay_status) def set_all_relay_onself, cmd=110): print "set all relays off " self.handler.writechrcmd)) time.sleepself.interval) self.get_relay_status)
附录
ZZR08 command Table
Command | Action | ||
Character | DEC | HEX | |
90 | 5A | Get software version – returns 2 bytes, the first being the module ID which is 8, followed by the software version |
|
91 | 5B | Get relay states – sends a single byte back to the controller, bit high meaning the corresponding relay is powered |
|
92 | 5C | Set relay states – the next single byte will set all relays states, All on = 255 11111111) ,All off = 0 |
|
d | 100 | 64 | All relays on |
e | 101 | 65 | Turn relay 1 on |
f | 102 | 66 | Turn relay 2 on |
g | 103 | 67 | Turn relay 3 on |
h | 104 | 68 | Turn relay 4 on |
i | 105 | 69 | Turn relay 5 on |
j | 106 | 6A | Turn relay 6 on |
k | 107 | 6B | Turn relay 7 on |
l | 108 | 6C | Turn relay 8 on |
n | 110 | 6E | All relays off |
o | 111 | 6F | Turn relay 1 off |
p | 112 | 70 | Turn relay 2 off |
q | 113 | 71 | Turn relay 3 off |
r | 114 | 72 | Turn relay 4 off |
s | 115 | 73 | Turn relay 5 off |
t | 116 | 74 | Turn relay 6 off |
u | 117 | 75 | Turn relay 7 off |
v | 118 | 76 | Turn relay 8 off |