Datasheet

PinD3throughD7areJTAGinterfacepins.ThesecanbeusedtoreprogramyourPhoton
bootloaderoruserfirmwareimagewithstandardJTAGtoolssuchastheST-Linkv2,J-Link,R-Link,
OLIMEXARM-USB-TINI-H,andalsotheFTDI-basedParticleJTAGProgrammer.Ifyouareshorton
availablepins,youmayalsouseSWDmodewhichrequireslessconnections.
Photon
Pin JTAG SWD
STM32F205RGY6
Pin
PØPin
# PØPinName
Default
Internal
[1]
D7 JTAG_TMS SWD/SWDIO PA13 44 MICRO_JTAG_TMS ~40kpull-up
D6 JTAG_TCK CLK/SWCLK PA14 40 MICRO_JTAG_TCK ~40kpull-down
D5 JTAG_TDI PA15 43 MICRO_JTAG_TDI ~40kpull-up
D4 JTAG_TDO PB3 41 MICRO_JTAG_TDO Floating
D3 JTAG_TRST PB4 42 MICRO_JTAG_TRSTN ~40kpull-up
3V3 Power Power
GND Ground Ground
RST Reset Reset
Notes:
[1]
DefaultstateafterresetforashortperiodoftimebeforethesepinsarerestoredtoGPIO
(ifJTAGdebuggingisnotrequired,i.e. USE_SWD_JTAG=y isnotspecifiedonthecommandline.)
Astandard20-pin0.1"shroudedmaleJTAGinterfaceconnectorshouldbewiredasfollows:
JTAGANDSWD