| ??? 08/28/13 22:30 Read: times |
#190011 - RST and Full speed ? Responding to: ???'s previous message |
Mikkel C. Simonsen said:
... I have discovered another bug/feature. If the supply voltage rises slowly, the internal oscillator runs at double speed sometimes. If the rise time is low, the problem doesn't happen. The IC is supposed to have an internal reset circuit, that should take care of this problem...
If you reload the Clock Divider on some pin change, or serial command, does that restore the expected operation ? The STC info suggests they defaulted to No-divide, which is not so clever on a slowly rising supply - the RST may release <before/u> the CPU can run at 35MHz. What voltage does it release RST at ? Most vendors default to a slower speed, then rise it later. The LP52 looks quite good here, because it is such a low speed, it seems to always be OK, even close to the 2.0V BOD level. I also found it wakes up well, on an external level, from sub 1uA Power Down. |
| Topic | Author | Date |
| STC 15F104E | 01/01/70 00:00 | |
| The STC12C5Axxx work fine | 01/01/70 00:00 | |
| Others | 01/01/70 00:00 | |
| Support from STC? | 01/01/70 00:00 | |
| Support? | 01/01/70 00:00 | |
| Just Email STC | 01/01/70 00:00 | |
| Who am I e-mailing? | 01/01/70 00:00 | |
| I guess SiliconRay is same as STC | 01/01/70 00:00 | |
| RST and Full speed ? | 01/01/70 00:00 | |
| Divider | 01/01/70 00:00 | |
LP52 | 01/01/70 00:00 | |
| USB programming works | 01/01/70 00:00 |