ftdi_spi doesn't appear to support chips with more than 8 GPIO's

System: Ubuntu 22.04 Linux Kernel: 5.15.0-48-generic Python version: 3.10.6

This is potentially an odd one, fringe case or even PICNIC.

I’m trying to utilise a SSD1322 OLED display through an FTDI FT232h USB adapter. The chip on the adapter has 2x GPIO banks (the usual ADBUS pins 0-7 labelled as D0-7, and the secondary ACBUS pins 0-7 labelled as pins C0-7)…

This used to work fine under Ubuntu 16.04 using the Adafruit_GPIO Python2.7 module to wrap the SPI interface (it provided an abstraction of FT232H) with the following pin configuration…

CS = 3     #D3 Brown
RESET = 13 #C5 Purple
DC = 14    #C6 White

…however this has been completely dropped and I’ve migrated to pyftdi to try and return to what the luma.core documents state. In migrating, I now find myself with this error:

pyftdi.spi.SpiIOError: No such GPO pins: 0000/2000

This is the code I’ve written to try and initialise it;

from luma.core.interface.serial import ftdi_spi
from luma.core.render import canvas
from luma.oled.device import ssd1322

SPI = ftdi_spi(device='ftdi://ftdi:232h:RP39WI7Z/1', bus_speed_hz=8E6, gpio_CS=3, gpio_DC=14, gpio_RST=13)

To which I get the following traceback;

Traceback (most recent call last):
  File "/root/src/oled-esxi/test.py", line 67, in <module>
    SPI = ftdi_spi(device='ftdi://ftdi:232h:RP39WI7Z/1', bus_speed_hz=8E6, gpio_CS=3, gpio_DC=14, gpio_RST=13)
  File "/root/src/oled-esxi/venv/lib/python3.10/site-packages/luma/core/interface/serial.py", line 495, in ftdi_spi
    serial = spi(
  File "/root/src/oled-esxi/venv/lib/python3.10/site-packages/luma/core/interface/serial.py", line 299, in __init__
    bitbang.__init__(self, gpio, transfer_size, reset_hold_time, reset_release_time, DC=gpio_DC, RST=gpio_RST)
  File "/root/src/oled-esxi/venv/lib/python3.10/site-packages/luma/core/interface/serial.py", line 195, in __init__
    self._gpio.output(self._RST, self._gpio.HIGH)  # Keep RESET pulled high
  File "/root/src/oled-esxi/venv/lib/python3.10/site-packages/luma/core/interface/serial.py", line 427, in output
    self._gpio.write(self._data)
  File "/root/src/oled-esxi/venv/lib/python3.10/site-packages/pyftdi/spi.py", line 316, in write
    return self._controller.write_gpio(value)
  File "/root/src/oled-esxi/venv/lib/python3.10/site-packages/pyftdi/spi.py", line 682, in write_gpio
    raise SpiIOError('No such GPO pins: %04x/%04x' %
pyftdi.spi.SpiIOError: No such GPO pins: 0000/2000

Sadly I cannot simply “rewire” - this was a small run custom PCB made by an Aida64 forum member and as such, immutable.

The pyftdi module references 16-bit wide GPIOs for the 232h so I know this is possible. Richard (or perhaps another developer), please can you look into this when you find yourself with a few mins? 🥰

[jasongaunt]

So Amazon managed to lose it…

Have chosen an alternative and it’s on its way; https://www.mouser.co.uk/ProductDetail/895-FT2232HMINIMOD

[thijstriemstra]

Pull request https://github.com/rm-hull/luma.core/pull/257 has been raised

Closing.