What Is ISP Pinout

ISP (In-System Programming) is a chip-level access method that allows technicians to communicate directly with the eMMC flash storage on a device's motherboard without removing the chip. By connecting a programmer to specific test pads — collectively called ISP pinout points — the tool can read, write, or erase data at the raw flash level. This is especially valuable when the device cannot boot normally, making software-based tools ineffective. The ISP method bypasses the Android OS entirely, giving repair professionals full access to firmware partitions, the userdata area, and the bootloader.

SM-A605 ISP Pinout Diagram

The Samsung SM-A605 (Galaxy A6 Plus 2018) uses an Exynos 7870 chipset paired with an eMMC 5.1 flash storage module. The ISP test points are located on the rear side of the motherboard, in the vicinity of the eMMC chip. The standard eMMC ISP interface uses the following signal lines:

  • CLK – Clock signal line; synchronises data transfer between programmer and eMMC
  • CMD – Command line; sends read/write/erase commands to the eMMC controller
  • DAT0 – Primary data line for single-bit communication during identification phase
  • VCC – Main power supply for the eMMC (typically 2.9 V–3.3 V)
  • VCCQ – I/O supply voltage for signal lines (typically 1.8 V)
  • GND – Ground reference for all signals
  • RST – Reset line; used to hard-reset the eMMC controller before communication

Note: Exact pad coordinates and silkscreen labels for the SM-A605 board have not been independently verified in public documentation. Technicians should cross-reference with a verified board schematic or a trusted ISP pad diagram image before soldering.

When Technicians Use ISP

ISP access on the SM-A605 is typically required in the following scenarios:

  • Dead Boot Repair – When the device shows no signs of life after a failed OTA update or interrupted flash
  • FRP (Factory Reset Protection) Bypass – When the Google account lock cannot be removed via conventional methods
  • Pattern / PIN Lock Removal – When the userdata partition needs to be wiped at chip level
  • IMEI Repair – Restoring corrupted or blank IMEI data by rewriting the relevant partitions
  • Full Firmware Read/Backup – Creating a full eMMC dump for restoration or forensic purposes

How to Access the Test Points

Follow this procedure when connecting an ISP programmer to the SM-A605:

  • Fully disassemble the device and safely remove the motherboard
  • Identify the eMMC chip on the rear side of the board using a reference diagram
  • Solder thin wire or use a dedicated ISP clip/fixture to the CLK, CMD, DAT0, VCC, VCCQ, GND, and RST pads
  • Connect wires to your programmer (e.g., EasyJTAG Plus or UMT ISP adapter)
  • Launch the programmer software, select the SM-A605 or Exynos 7870 profile, and set voltages to match the eMMC spec (VCC: 3.0 V, VCCQ: 1.8 V)
  • Initiate the desired operation (read, erase, or write)

Safety Tips and Precautions

ISP work carries significant risk if done incorrectly. Follow these precautions:

  • Always verify voltage settings before powering the board — incorrect voltage will permanently damage the eMMC
  • Double-check pad connections for shorts before applying power; a short on CMD or CLK can brick the device
  • Back up the full eMMC dump before performing any write or erase operation
  • Use a quality regulated power supply — do not rely solely on the programmer's onboard power for VCC
  • Work in an ESD-safe environment with a grounded wrist strap to prevent static discharge damage

Pin / Test Point Reference

PinDescription
CLKClock signal for eMMC communication — Exact pad location unverified; cross-reference board schematic
CMDCommand line for read/write/erase instructions — Exact pad location unverified
DAT0Primary data line used during eMMC initialisation — Exact pad location unverified
VCCeMMC main power supply — typically 3.0 V — Verify with board schematic before applying power
VCCQI/O signal voltage supply — typically 1.8 V — Exact pad location unverified
GNDGround reference pad — Multiple GND points available on board
RSTeMMC reset line — Exact pad location unverified; not always required by all programmers

Tools required: EasyJTAG Plus, UMT ISP Adapter, Medusa Pro II, RIFF Box 2, JIG ISP Adapter (eMMC 5.1 compatible), Fine-tip soldering iron, Regulated DC power supply

Supported operations: Read Firmware (Full eMMC Dump), Write Firmware, FRP Erase, Dead Boot Repair, Pattern/PIN Lock Removal, IMEI Repair, Userdata Wipe

⚠ Safety note: Use correct voltages only (VCC 3.0 V, VCCQ 1.8 V). Incorrect voltage or a short circuit will permanently damage the eMMC. Always back up before writing. Work ESD-safe.