Hello Philipp, Saturday, August 5, 2017, 8:41:42 PM, you wrote:
PS> Yes, you're probably right. PS> Though I wonder when and how they programmed the firmware. Before or PS> after soldering? Most likely before, unless they have some debug header exposed. From [1]: > When the hardware and software nears production readiness, it is > common practice to preprogram flash memory devices prior to > starting high-volume PCB manufacturing flows for two principal > reasons. First, firmware loaded onto the device can be used to > perform basic booting and testing of the PCB during manufacturing > to check system/module functionality. Second, loading the final > firmware, operating system (OS), and application code on the flash > device prior to manufacturing maintains a high-volume > manufacturing beat rate. To support these usage models, multiple > vendors provide systems for loading firmware and data into flash > memory devices prior to the PCB solder flow process. Modern flash chips don't have issues retaining programmed bits during reflow soldering as long as the correct temperature profile is observed [2]. [1]: http://www.electronicdesign.com/memory/understanding-onboard-flash-programming [2]: http://dataioinfo.com/LiveImages/26/20/DocumentURL.pdf -- WBR, Igor mailto:[email protected] -- coreboot mailing list: [email protected] https://mail.coreboot.org/mailman/listinfo/coreboot
