ARM CoreSight 10-pin

ARM Cortex 10-Pin 0.05-inch (1.27mm) Micro Debug & SWD Header

The 10-pin Cortex debug header is the compact 1.27 mm connector for Serial Wire Debug and JTAG on Arm Cortex-M boards. Select a contact to see its SWD and JTAG function.

Pin assignment

Pin 1: VTREF1Pin 3: GND3Pin 5: GND5Pin 7: KEY7Pin 9: GND9Pin 2: SWDIO / TMS2Pin 4: SWCLK / TCK4Pin 6: SWO / TDO6Pin 8: TDI8Pin 10: nSRST10Pin 1: VTREF1Pin 3: GND3Pin 5: GND5Pin 7: KEY7Pin 9: GND9Pin 2: SWDIO / TMS2Pin 4: SWCLK / TCK4Pin 6: SWO / TDO6Pin 8: TDI8Pin 10: nSRST10
  • Power
  • Debug (JTAG/SWD)
  • Ground
  • Not connected

Schematic face view, not to scale · numbering per ARM CoreSight 10-pin

Pin assignment of ARM Cortex 10-Pin SWD Header
PinSignalFunctionStatus
VTREFTarget reference voltage: the probe matches its logic levels to it and detects the target when it exceeds 0.8 VStandard
SWDIO / TMSSerial Wire debug data I/O / JTAG test mode selectStandard
GNDGroundStandard
SWCLK / TCKSerial Wire clock / JTAG test clockStandard
GNDGroundStandard
SWO / TDOSerial Wire trace output / JTAG test data outStandard
KEYPolarization key: no pin, not connectedDiscretionary
TDIJTAG test data in (unused in Serial Wire mode)Standard
GNDGround; Keil documentation calls it GNDDetect, used by the probe to sense a connected targetStandard
nSRSTTarget system reset, active low (nRESET in Keil documentation)Standard

Pin details

Select a pin on the diagram or table for full details.

Pin details

About this connector

Compact 10-pin ARM Cortex debug connector for SWD, optional trace, target reset, reference voltage, and ground.

Specifications

Standard
ARM Cortex 10-Pin 1.27mm Pitch
Positions
10

Primary sources

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