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« on: March 25, 2021, 10:57:04 am »
Hello,
I use the FTDI cable C232HM-DDHSL-0 that has the FTDI chip FT232H. I use D2XX driver for Linux.
In D2XX Programmer's Guide (in its latest version 1.4) the description of the function FT_SetBitmode states:
"ucMask Required value for bit mode mask. This sets up which bits are inputs and outputs. A bit value of 0 sets the corresponding pin to an input, a bit value of 1 sets the corresponding pin to an output".
I would like to know what pins of FT232H chip are configured in accordance with ucMask when the function FT_SetBitmode is called? I assume that these are pins ADBUS0..ADBUS7, but I cannot find the confirmation of it in FTDI documentation: I have looked for it in the datasheet for FT232H chip, in D2XX Programmer's Guide, and in FTDI Application Notes 108, 129, 135.
Please advise if this information is covered somewhere in FTDI documentation?
Do I understand correctly that after the call FT_SetBitmode(ftHandle, 0x0, 0x0) all the pins ADBUS0..ADBUS7 of FT232H chip (and the corresponding wires of the C232HM cable) will be configured as inputs?
P.S. I would like to know it because I am going to configure all FT232H pins as inputs until my target device (which I am going to debug with JTAG) is initialized and ready for JTAG communication. It would allow to avoid a possible short circuit in the case if some pins of my target device are configured as outputs in the timeframe after the device is powered on and before it is initialized for JTAG communication. After the target device is ready for JTAG communication I am going to switch FT232H chip to MPSSE mode and then configure pins directions for JTAG communication by means of MPSSE commands.
Thank you in advance!