[time-nuts] FE-5680A programming connector pinout

Elio Corbolante eliocor at gmail.com
Thu Feb 2 01:50:38 UTC 2012

The 15 pin connector (near crystal oscillator) is used for JTAG programming
the XC8572XL (XC) and the PSD813F1V (PSD).
According to my analysis the pinout is the following:

1) Vcc/+5V - goes to pin 5 of MAX882 voltage regulator: its 3.3V output
powers XC and PSD
2) Ground (GND)
3) PSD pin PC6 (JTAG-TDO)
4) PSD pin PC5 (JTAG-TDI)
5) PSD pin PC4 (JTAG-/TERR) [on datasheet erroneously shown connected to
6) PSD pin PC3 (JTAG-/TSTAT)
7) PSD pin PC1 (JTAG-TCK)
8) PSD pin PC0 (JTAG-TMS)
9) no known connection
10) no known connection
11) XC pin 30 (JTAG-TCK)
12) XC pin 28 (JTAG-TDI)
13) XC pin 53 (JTAG-TDO)
14) XC pin 29 (JTAG-TMS)
15) no known connection

I think the +5V on pin 1 should be enough to program the two chips without
requiring any power on the DB9 connector.

My MQP Pin-Master 48 programmer SHOULD be able (via JTAG) to read the
FLASH/EEPROM contents of the PSD813F1V: during the weekend I will try to
dump the firmware of the FE-5680A.
If the PSD chip is JTAG read protected I will have to desolder it and try
to read its contents directly accessing Address/Data lines.

at the following address you will find a (rather big) annotated picture
regarding the connector pinout:

_       Elio Corbolante.

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