Re: [avrdude-dev] Re: Implementation of of FTD2XX-based AVR programmer in avrdude

[Johnathan Corgan]

Uwe Bonnes wrote:

> Try setting it to 2 ms. For me, 1 ms had no effect.

No effect.  Nor did 10 ms.

I'm not certain this parameter is the problem anyway.  My understanding 
is the latency timer governs how long to wait for further user writes 
before sending an incomplete buffer.

In this case the delay seems to be a turn-around issue.  I'm sending a 
byte with SCLK low using FT_Write, then reading a byte with 
FT_GetBitMode for the pin status, then sending a byte with SCLK high, 
etc. Maybe it's the case that there is a receive latency timer in the 
hardware that isn't settable, and that's where the delay is.

Anyway, that's probably enough FTDI specific email traffic for the list. 
 When I get back from my trip I'll dive into this with a fresh mind, 
and set up a support call with FTDI if needed.

I may hack in a flag into avrpart.h that indicates whether each command 
needs a result, and take advantage of that in pgm->cmd() to batch write 
the 32 bits and fake a response value.

-Johnathan