jtag - FTDI D2xx Read TCK value - Stack Overflow

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I have a problem with ftdi (D2xx library).

I am using the D2xx (ftd2xx) library to control an FTDI FT2232H chip and configure it as JTAG.

To set the TCK clock, I use opcode 0x86 as follows:

// Command to set clock divisor
byOutputBuffer[dwNumBytesToSend++] = 0x86;
// Low byte of clock divisor
byOutputBuffer[dwNumBytesToSend++] = clk_div & 0xFF;
// High byte of clock divisor
byOutputBuffer[dwNumBytesToSend++] = (clk_div >> 8) & 0xFF;

// Send clock divisor commands
g_pWrite(ftHandle_, byOutputBuffer, dwNumBytesToSend, &dwNumBytesSent);

This works correctly.

Now, I need to read the configured TCK clock (divider).

I have tried the following:

// Command to set clock divisor
byOutputBuffer[dwNumBytesToSend++] = 0x86;
g_pWrite(ftHandle_, byOutputBuffer, dwNumBytesToSend, &dwNumBytesSent);

// Check the number of bytes written
printf("Number of bytes written: %d\n", dwNumBytesSent);

do {
    ftStatus = g_pGetQueueStatus(ftHandle_, &dwNumBytesToRead);
} while ((dwNumBytesToRead == 0) && (ftStatus == FT_OK));

printf("ftdi_blaster::get_freq : Bytes received = %d\n", dwNumBytesToRead);

However, the number of bytes received (dwNumBytesToRead) is always 0.

How can I correctly read the configured clock divisor?

thanks.

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