WISMO_ready; what does it mean exactly?

Hi All,

It takes 4 to 7 seconds before Wismo_ready becomes active after an cold boot. According to the datasheet of the WS6318, after 185ms it starts doing power-key debouncing for like 500ms and then “normal software”. But between normal SW and wismo_ready there is still a time gap of like many seconds.
I measure 3 seconds after Vbat-on to wismo_ready, so beyond the minimum stated in the specs. Also strange.

My application is pretty simple:
With the least amount of energy:

  • power-up the WS6318
  • AT send an SMS (no reception necessary)
  • de-power the WS6315

A wismo_ready of 4 to 7 or the measured 3 seconds , is quite some energy already.
My question:

  • can we shorten thr ready time?
  • does it wismo_ready also means registered to a provider?


Hi Edwin,

I think the actual time depends on FW, not much we can do but the SW may get optimized such that time needed for Tready(Table 34 on PTS) may vary, maybe you can try to use latest FW.
Still as mentioned in PTS section Power On:
“WISMO_READY pin will be set to HIGH level to acknowledge the successful power ON of the WS6318 embedded module”

So, it is just an indication that bootup (HW/SW initialization) is completed, it does not cover the time needed for network registration.

How often you want to send the SMS? Maybe you can make use of the sleep mode if you are sending frequently?

Hope this helps.

Hi Lotam,

Thanx sofar. We think just in a couple of sms per day. So ranging from 1 to 10. The total GSM circuitry also contains dc-dc convertor to limit the current drawn from the lipo battery. The interval is pretty long so sleep would consume too much energy for the whole circuitry.

Should wismo-ready also be used as a signal -when- the serial communication lines may become active? There’s a caution statement in section 5.1 that external signals should be inactive when the module power is off. That is pretty clear I would say. But what during the power-on sequence?


Hi Edwin,

Agree if you are sending just a couple of SMS per day, maybe good to try using latest FW to see any improvement in boot time.

I assume WS6318 is ready when WISMO_READY is up, if you want to play safe, you can check the CTS signal and in additional sending “AT\r” to test any response from module.

For UART signals, I found it mentioned in PTS section

Make sure that the TXD, RTS and DTR signals of UART1 and UART2 are set to low level until the VBATT voltage is over 3.2V and stable for at least 60ms.

So, maybe we can instead wait WISMO_READY as indication.

Hope this helps.

Thanks again. I’ll check the latest FW.

Hi Lotam,

What about firmware upgrading the WS6318. It look like it’s kept as a corporate secret!
I need all information what I can get how to firmware upgrade the WS6318 in my own application.

  • Which hardware signals do I need to have available for attachment?
  • if, which specific signal sequence is needed?
  • what program should I use
    etc etc.