Quote:
Originally Posted by Argo_Andrew  There is no description of JTAG connector in this manual. |
in i900 i think that this phones Jtag pins avaliable in the main phone charge/handsfree/Usb soocket.
in the original I900 service manual description of Jtag pinout shown in page 68 as below:
IFC400 : main phone external conector
pin18 : Jtag_VBUS
pin15 : Jtag_con_sense ( I think this pin work as testpoint for activate Jtag)
pin 12 : Jtag_RXD
in this case we haven't desription for Jtag TXD ( or DI ) and i think ( this is my sight ) it must be pin11 ( share as same TXD in datasheet)
if this be a standard Jtag we must have TMS AND TCK pins for compllete.
but in many case ( of standard Jtags ) we can remove TMS ( because it is for reset target and you can do this by instruction reset )
but TCK !
i think in this case we have a non-standard Jtag and clock must generate from RTC of CPU,
we only wants to
1- know RTC of this cpu have standard clock ( 32.768Khz ) or another clocktime? ( in PXAxxx we have another free clock source 10Mhz and Jtag clock may be it )
2- nand flash address , eboot file ,start address for write eboot and one program can support chain programing via PXA31X CPU?
another theory ( i think this must be very likly)
for this phone with this Jtag pinout we only use Jtag connection for send instruction to CPU and start it,
after this CPU go to Conecting modem form via USB and we able for programig mode via Standard USB connection ( this CPU support this programing harware form )
*in service manual I900 Jtag( or JIG cable shown with this partnumber: GH39-00993A and its originaly for samy-I780!
looking for your ideas