Command Read/Write
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-To read/write to RAM, need to send a commands to the device.
+To read/write to RAM, need to send a command to the device.
The command format is as below.
Byte7 Checksum
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-Command Byte is read=0xD1/write=0xD2 .
+Command Byte is read=0xD1/write=0xD2.
Address is read/write RAM address.