| Hao Huan wrote: |
|
By the way I have another question: when the default operation mode of the DRS4 chip is used, i.e. WSRIN is fed internally to WSROUT, at the external pins is it necessary to leave the WSRIN open? Or any input through the pin will not affect the Domino wave running? Also I observe that WSROUT will be always low when the chip is running in this mode; is it the supposed behavior?
|
If the WSRin is fed internally to WSROUT, then the level of the WSRIN pin does not matter, it's just disconnected. You can leave the pin open without problem. WSROUT is however active, so you can observe the internal state of the write shift register. In the default configuration (8x1024 sampling cells), all 8 channels are active all the time, so the WSR is loaded with ones. The inverter at the output then makes all zeros from this. If you configure the chip as 4x2048 cells, then you will observe switching bits at WSROUT. |