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eblot / pyftdi

FTDI device driver written in pure Python
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F232H - Lock on High State for CBUS pins #236

Open kelyrr opened 3 years ago

kelyrr commented 3 years ago

Hello,

Hello

With FTPROG i have switched the cbus_0 on "DRIVE1" and the LED turned on. Then i switched to "DRIVE0" but the LED stays into HIGH state.

Please could you explain why this is happening ? What should i do ?

Also, i have difficult to understand what i should put into theses functions to control the GPIOs: image

Thanks a lot for your help!! :) Clément

eblot commented 3 years ago

Whenever you update the EEPROM, you need to power cycle the device so that the EEPROM content is read and used.

Usage example on an UM232H board (FT232H module):

  1. Load the current EEPROM content into a file pyftdi/bin/ftconf.py -P 15ba:002a -o ft232h.ini ftdi://:232h/1

  2. Create a backup file if something goes wrong cp ft232h.ini ft232h_backup.ini

  3. Edit the INI file

    [values]
; ...
cbus_func_8 = DRIVE0
cbus_func_9 = DRIVE1

  4. Update the EEPROM pyftdi/bin/ftconf.py -i ft232h.ini -l values -u ftdi://:232h/1

  5. Unplug/plug back the UM232H module

    • yellow led lights up, green led is off

  6. Edit the INI file

    [values]
; ...
cbus_func_8 = DRIVE1
cbus_func_9 = DRIVE0

  7. Update the EEPROM pyftdi/bin/ftconf.py -i ft232h.ini -l values -u ftdi://:232h/1

  8. Unplug/plug back the UM232H module

    • green led lights up, yellow led is off

  9. Edit the INI file

    [values]
; ...
cbus_func_8 = GPIO
cbus_func_9 = GPIO

  10. Unplug/plug back the UM232H module

    • Now the module is ready to accept CBUS commands, so that AC8 and AC9 output can be changed dynamically

  11. Run a small Python test On FT232H, CBUS drivable pins are ACBUS5, ACBUS6,ACBUS8, ACBUS9, from FT232H datasheet, therefore:

    • AC5 is b0, AC6 is b1, AC8 is b3, AC9 is b4.
    • to use AC8 and AC9, the mask is therefore 0b1100 or 0x0c; to use GPIO as output, the direction is 0xc as well 
      
#!/usr/bin/env python3

    from time import sleep from pyftdi.ftdi import Ftdi, FtdiError from pyftdi.eeprom import FtdiEeprom

    ftdi = Ftdi() ftdi.open_from_url('ftdi://:232h/1')

    sanity check: device should support CBUS feature

    assert(ftdi.has_cbus == True) eeprom = FtdiEeprom() eeprom.connect(ftdi)

    sanity check: device should have been configured for CBUS GPIOs

    assert(eeprom.cbus_mask & 0xc == 0xc)

    configure CBUS8 and CBUS9 as output

    ftdi.set_cbus_direction(0xc, 0xc) loop = 10

    alternate led blinking

    while loop: loop -= 1 ftdi.set_cbus_gpio(0x8) sleep(0.2) ftdi.set_cbus_gpio(0x4) sleep(0.2) ftdi.close()

    
![ft232h_led_cbus](https://user-images.githubusercontent.com/172423/117330849-65223480-ae96-11eb-9aee-e2a0ba97a10f.gif)
jbkroner commented 3 years ago

I don't have any questions. I just want to thank you for the great example you've left in this thread @eblot! 👏

Zibri commented 2 years ago 
ftdi.set_cbus_gpio(0x8)

My FT232R is configured in this way: image

But,

eeprom.cbus_mask 0

What should I do to access the 2 LEDS from python?