I've seen, quite often actually, a circuit that will have an eeprom or flash chip soldered next to the application chip. Take a look at the ESP8266, it has some kind of programmable memory that sets up the SoC.

My question is how was that eeprom/flash chip programmed if there aren't any programming ports on the application board? Is there like some pogo-pin programmer used during assembly or a socket that they drop each and every one in before soldering? Those options seem incredibly time consuming.

  • 2
    \$\begingroup\$ For sufficient volume, manufacturers offer programming as a service. Dave ran into a problem with it a while back. youtube.com/watch?v=yPdeAk17Vys \$\endgroup\$
    – Matt Young
    Jan 5, 2016 at 21:36
  • \$\begingroup\$ Please post a link to the board. For the sake of accuracy: an ESP8266 does not have an ARM controller. It is a Tensilica Xtensa LX106. The memory chip is likely not an EEPROM, it is likely Flash (often Quad-SPI), which is a different technology. I agree with DoxyLover. However, also for the sake of clarity, the ESP8266 has an on-board bootloader in ROM. AFAIK, the ESP8266 can program the external flash from its UART. \$\endgroup\$
    – gbulmer
    Jan 5, 2016 at 23:24

1 Answer 1


I can't speak for the ESP8266, but in most cases, the blank chips are sent to a programming house that has equipment to mass-program them, either in a row of sockets or, in the case of large production runs, with an automated system that automatically runs each chip through the programmer.

In many cases, the board assembly house contracts with the programming house to provide the programmed chips.


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