There is a SPI to USB bridge by Microchip, MCP2210 maybe it helps if you need master: http://www.microchip.com/wwwproducts/Devices.aspx?product=MCP2210
also a lot of free projects about SPI sniffers as Bus Pirate. Also check the FTDI: http://www.ftdichip.com/Support/SoftwareExamples/MPSSE/FT2232C-Proj01_v11.pdf Vasile On Sat, Aug 16, 2014 at 4:28 AM, Pavel Milanes Costa <[email protected]> wrote: > Hi to all... > > Note: if not interested in why I want to buid a SPI sniffer skip to where > say: *I HAVE TRIED THIS:* > > I'm a ham radio (CO7WT) and I have two fine transceivers that are dead for > the MCU of the radio... (Yaesu FT-747GX) all the other electronicas are > just fine... but the "brain" is dead > > I have one working radio of that and I use it for experimenting/hacking, > please not that in Cuba there is not a free/open market for ham radios, so > by another is not an option... > > And hacking is a very pleasant/instructive work :-) > > Yes I have writed (email) to Yaesu and the former manufacturer of the > 7925B IC: dead end. > > I have hacked (reverse engineering) all the electronics and signalling but > the way the MCU speaks with the two PLL... (one for big steps an the other > for small steps...) > > I need the datasheet or any form of how to speak with the 7925B IC > (Japanese PLL IC)... > > From the radio's tech manual and with a lot of math I have deduced the > math involved to calc the data I need to send to the TWO PLL ICs but I > can't talk the 7925B dialect !!! > > The internet was not of help on find any clue about the 7925B as it's > discontinued part a long ago... > > So I have decided to sniff the SPI code... but, ho boy!!!, it's harder > than I think in the first place... > > I have a PICKIT2 clone and I tried to use the debug function: no joy... > the bus appears to run at 1Mhz... I know that it's about 40 bits... to each > IC... I get a random number of bits on each try... > > *I HAVE TRIED THIS:* > > PIC for the job is a PIC18F25K22 from a jalunio bee board... full 64 Mhz > with x4 PLL, it's running at 16Mhz real clock (64/4) > > 1 - Detect the CLK change and the read the data and two latches, then send > it by serial at full speed (115,200 kbps) > > No joy, the serial Tx is blocking or overriding the detection, just > detected about 8 to 10 bits per Tx from the MCU... > > 2 - Detect the CLK change and the read the data and two latches, store in > a I2C EERPOM (CLK+DAT+L1+L2 = 4 bits), so I split each byte in a 4 bit > positions... Then when 24LC32 is full dump it by serial... > > No joy... about 5 bits per tx, the write in the I2C eeprom is too SLOW for > the job.. > > 3 - Detect the CLK change and the read the data and two latches, store it > on a memory array, when full dump by serie... > > better but no joy yet... about 15 to 20 bits per tx... it appears the TX > is very fast for the sensing-store procedure... > > The Original MCU is clocked at 4Mhz by a ceramic resonator... I guess they > are running at 1Mhz and sending the SPI at full speed. > > Any ideas for this hacking project about revive and old and good radio > with a new "PIC brain?" > > Cheers from Pavel, CO7WT. > > > > > -- > You received this message because you are subscribed to the Google Groups > "jallib" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > To post to this group, send email to [email protected]. > Visit this group at http://groups.google.com/group/jallib. > For more options, visit https://groups.google.com/d/optout. > -- You received this message because you are subscribed to the Google Groups "jallib" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at http://groups.google.com/group/jallib. For more options, visit https://groups.google.com/d/optout.
