When I tried to jtag my DS101, I found out that it's a little bit more complicated than just plugging in the cable and then running jtag software. I'll use this page to capture my findings, in a log format initially. ---Steven.

20061222.

• jtag worked, but got into another issue.
• got device id right, "detectflash" reported flash info, then power is switched off all in a sudden.
• jtag pinout as below:

 
	1-VCC
	2-nTRST
	3-TDI
	4-TMS
	5-TCK
	6-GND
	7-TDO
	8-NC (not connected)

20061223.

• did some investigations on the power supply of the board

20061227

• soldered a jumper on the power button - equivalent of pushing power button - to work around the power off problem of the jtag
• backed up flash memory through jtag

20061228

• burned a re-compiled redboot, no console output
• burned a prebuit redboot, no console output
• burned the backed-up redboot, console ok

20061229

• burned a re-compiled u-boot, no console output
• burned a prebuilt u-boot, no console output
• burned a re-compiled apex, no console output
• burned a prebuilt apex, no console output

20061230

• fixed byte swapping script (between 2 and 4 bytes)
• burned a apex, got console output
• burned a u-boot, got console output
• burned the backed-up redboot, re-initialized fis.

Conclusions

• Those tests convinced me that my jtag tool is in a usable condition, and this concludes my jtag tests.
• my jtag tool is quite slow, a better solution is called for if jtag will be used more often.

Hardware, Software and Misc.

• Synology DS-101, PCB rev 3.0, firmware V.30
• the flash chip is an Intel 28F128J3A, not a DiskOnChip?
• the device was acquired circa Oct. 2006.
• the jtag adapter is generic, some wiring was done to make it Wiggler compatible.
• the jtag software is openwince jtag0.5.1, with a patch by Stewart Heitmann.
• thanks for helps on information, software and patches from websites, forums and mailing lists.
• thanks for helps of my friends on adapters and connectors and such.
• further work would be to pick a bootloader, put on a kernel and run as a server.