4 ms·
Very cool! A few questions: How was the 696 MHz DDR3 RAM speed determined? Also, how is the system initialized at startup? Is there boot/startup code, does
by peter_d_sherman 10mo ago
Very cool!
A few questions:
How was the 696 MHz DDR3 RAM speed determined?
Also, how is the system initialized at startup? Is there boot/startup code, does that exist in a flash chip (or some other ROM or EEPROM or flash type chip) on the system, and can the boot code be inspected/customized/overwritten by the end-user? How does the system boot?
Anyway, looks very cool!
- Cyao 10mo agoThanks! I used the orange pi pc fel tester [1] and gradually lowered the clock speed until it became stable. When I got to 696 MHz the test ran for more than 3 hours without problems. The H3 CPU has a small bootloader inside, that enumerated the SD card and eMMC to look for a user-made bootloader. IIRC it looks for some file inside of the file system, and loads it to 0x70000. Thus you can customize it if you have enough time :) [1] https://github.com/ssvb/lima-memtester/releases/tag/20151207-orange-pi-pc-fel-test https://github.com/ssvb/lima-memtester/releases/tag/20151207...
- peter_d_sherman 10mo agoInteresting, and very cool!