# simplePicoRfV10.py  tlfong01  2021oct28hkt1150
    #
    # Pico GP Pin Assignment
    #   GP0 = UART0 TxD = FS1000S    
    #   GP1 = UART0 RxD = MX05V 
    # Setup
    #   1. To loop back, short TxD pin to RxD pin
    #   2. To test Xmit/Recv, connect GP0 pin to FS1000S (Note 1), GP1 pin to MX05V
    # Note 1
    #   Warning: Pico 3V3 Gp0 pin direct connecting to 5V FS1000S data pin, might cause "latching up", and fry Pico (5% chance).
    # Note 2
    #   Suggestions
    #   1. Use HCT125 or HC03 to shift 3V3 logical level to 5V.
    #   2. Use 12V to power FS1000S to increae xmit power and therefore longer effective distance
    # References
    #   1. MicroPython Class UART – duplex serial communication bus
    #        https://docs.micropython.org/en/latest/library/machine.UART.html
    #   2. General information about the RP2xxx port
    #        https://docs.micropython.org/en/latest/rp2/general.html
    
    from machine import UART, Pin
    import utime
    
    uart0 = UART(0, baudrate = 1200, tx=Pin(0), rx=Pin(1))
    
    def testUartLoopBackV01():
        print('Begin testUartLoopBackV01(), ...')
        testMsg = 'Hello World'
        print('  writeTestMsg =', testMsg)
        uart0.write(testMsg)  # write 5 bytes
        utime.sleep(0.5)
        bytesRead = uart0.read(20) # read up to 5 bytes
        print('  bytes read =', bytesRead)
        print('End   testUartLoopBackV01().')
        return
    
    def testUartLoopBackV02():
        print('Begin testUartLoopBackV02(), ...')
        #testMsg = 'Hello World'
        testBytes = b'\0x5b\0xb5'
        print('  bytes written               =', testBytes)
        uart0.write(testBytes)  
        utime.sleep(0.5)
        bytesRead = uart0.read(20) # 
        print('  bytes read                  =', bytesRead)
        print('  Begin repeat printing bytes =', testBytes)    
        for count in range(100000):
            uart0.write(testBytes)
            utime.sleep(0.01)
        print('  End   repeat printing bytes =', testBytes)        
        print('End   testUartLoopBackV02().')
        return
    
    def testPicoFs1000aV06():
        print('Begin Pico TxD (GP0) driving FS1000A, ...')
        testBytes = b'\0x55\0x55' 
        for count in range(100000):
            uart0.write(testBytes)
            utime.sleep(0.01)     
        print('End   Pico TxD (GP0) driving FS1000A.')
        return
    
    def testPicoDirectDriveFs1000sV07():
        print('Begin Pico TxD (GP0) direct drive FS1000S, ...')
        testBytes = b'\0x55\0x55\0x55\0x55\0x55\0x55\0x55\0x55' 
        for count in range(100000):
            uart0.write(testBytes)
            utime.sleep(0.01)     
        print('End   Pico GP0 direct drive FS1000S.')
        return
    
    def testFs1000aMx05vV08():
        print('Begin testFs1000aMx05vV08(), ...')
        testBytes = b'\0x55\0x55\0x55\0x55\0x55\0x55\0x55\0x55'
        
        uart0.write(testBytes) # flush output
        uart0.read()           # flush Input
        
        print('  bytes written to   GP0 (UART0 TxD), connected to FS1000S =', testBytes)  
        uart0.write(testBytes)
        
        utime.sleep(0.5)
        
        bytesRead = uart0.read(8)    
        print('  bytes read    from GP1 (UART0 RxD), connected to MX05V   =', bytesRead)      
        
        print('End testFs1000sMx05vV05().')  
        return
    
    def testXmitRecvV09():
        
        print('Begin testXmitRecvV09(), ...')
        
        uart0.write(b'\0x00\0xff\0x00\0xff\0x00\0xff\0x00\0xff') # flush output
        utime.sleep(0.5)
        uart0.read()                                             # flush Input
    
        testBytes = b'\0x5b\0xb5\0x5b\0xb5\0x5b\0xb5\0x5b\0xb5'
        print('  bytes written               =', testBytes)
        uart0.write(testBytes)  
        
        utime.sleep(0.5)
        
        bytesRead = uart0.read(32)  
        print('  bytes read                  =', bytesRead)             
        
        print('End   testXmitRecvV09().')
        
        return
    
    # *** Main ***
    
    #testUartLoopBackV01() # GP0, GP1 loopback 'Hello World"
    #testUartLoopBackV02() # GP0, GP1 loopback'\x00x5b\x00xb5', also repeat send 
    testXmitRecvV09()    
    
    # .END
    
    ''' *** Sample output ***
    >>> %Run -c $EDITOR_CONTENT
    Begin testXmitRecvV09(), ...
      bytes written               = b'\x00x5b\x00xb5\x00x5b\x00xb5\x00x5b\x00xb5\x00x5b\x00xb5'
      bytes read                  = b'\x00\x00`\x00xb5\x00x5b\x00xb5\x00x5b\x00xb5\x00x5b\x00xb5\x1f'
    End   testXmitRecvV09().
    
    Begin testXmitRecvV09(), ...
      bytes written               = b'\x00x5b\x00xb5\x00x5b\x00xb5\x00x5b\x00xb5\x00x5b\x00xb5'
      bytes read                  = b'\x00\x10\x01\xe1\x89\xd5\x01\xe1\xd5\x89\x01\xe1\x89\xd5\x01\xe1\xd5\x89\x01\xe1\x89\xd5\x01\xe1\xd5\x89\x01\xe1\x89\xd5\xff\x07'
    End   testXmitRecvV09().
    
    '''