[OT] Reason for delay at GSM cellphone startup ?

Started by Anton Erasmus June 12, 2004
Hi,

Anyone doing work on GSM cellphones ? 
All the GSM cellphones I have used, cannot search for a phone number
for something like 10 to 20 seconds after the link has been
established at switchon.  What is so resource hungry that a simple
search through the addressbook cannot be done during this time ?
Even the GSM modules I have used behaves the same.

Regards
   Anton Erasmus
Anton Erasmus <spam@spam.spam> wrote:

> All the GSM cellphones I have used, cannot search for a phone number > for something like 10 to 20 seconds after the link has been > established at switchon. What is so resource hungry that a simple > search through the addressbook cannot be done during this time ?
AFAIK, that's not a problem of some procedure hogging the the CPU for that long (if it were, the length of this pause would depend on the age of the phone, as their processors keep getting faster each year). It's simply that the interface between the phone and the SIM card, where at least a part of those numbers are stored, is so slow that it takes a couple of seconds to copy its contents into RAM. And they don't even try to let you use the addressbook before that's completed. -- Hans-Bernhard Broeker (broeker@physik.rwth-aachen.de) Even if all the snow were burnt, ashes would remain.
On 12 Jun 2004 19:23:21 GMT, Hans-Bernhard Broeker
<broeker@physik.rwth-aachen.de> wrote:

>Anton Erasmus <spam@spam.spam> wrote: > >> All the GSM cellphones I have used, cannot search for a phone number >> for something like 10 to 20 seconds after the link has been >> established at switchon. What is so resource hungry that a simple >> search through the addressbook cannot be done during this time ? > >AFAIK, that's not a problem of some procedure hogging the the CPU for >that long (if it were, the length of this pause would depend on the >age of the phone, as their processors keep getting faster each year). >It's simply that the interface between the phone and the SIM card, >where at least a part of those numbers are stored, is so slow that it >takes a couple of seconds to copy its contents into RAM. And they don't >even try to let you use the addressbook before that's completed.
Even with a slow 1MHz clock for a SPI EEPROM, it should not take more than 0.5 seconds to read 32K. The delays I have seen are tens of seconds. Regards Anton Erasmus
"Anton Erasmus" <spam@spam.spam> wrote in message
news:mnnmc09hr01dn7ug01c8j2q0t6mq3c33ur@4ax.com...
> Even with a slow 1MHz clock for a SPI EEPROM, it should not take > more than 0.5 seconds to read 32K. The delays I have seen are tens of > seconds.
That might be true, but at what clock rate is the phone reading the card? My phone clearly tells it on the display that it is reading the phonebook from the card. Meindert

"Anton Erasmus" <spam@spam.spam> skrev i meddelandet
news:i9lmc0l93u8dm92ig6gouku89gatk2ir4f@4ax.com...
> Hi, > > Anyone doing work on GSM cellphones ? > All the GSM cellphones I have used, cannot search for a phone number > for something like 10 to 20 seconds after the link has been > established at switchon. What is so resource hungry that a simple > search through the addressbook cannot be done during this time ? > Even the GSM modules I have used behaves the same. > > Regards > Anton Erasmus
The address book is on the SIM card, and you have the ISO7816 interface which is not very fast. 9600 BAUD typically, maybe up to 115 kBaud. -- Best Regards, Ulf Samuelsson ulf@a-t-m-e-l.com This is a personal view which may or may not be share by my Employer Atmel Nordic AB
On Sun, 13 Jun 2004 00:35:44 +0200, "Ulf Samuelsson"
<ulf@atmel.nospam.com> wrote:

> > >"Anton Erasmus" <spam@spam.spam> skrev i meddelandet >news:i9lmc0l93u8dm92ig6gouku89gatk2ir4f@4ax.com... >> Hi, >> >> Anyone doing work on GSM cellphones ? >> All the GSM cellphones I have used, cannot search for a phone number >> for something like 10 to 20 seconds after the link has been >> established at switchon. What is so resource hungry that a simple >> search through the addressbook cannot be done during this time ? >> Even the GSM modules I have used behaves the same. >> >> Regards >> Anton Erasmus > >The address book is on the SIM card, and you have the ISO7816 interface >which is not very fast. 9600 BAUD typically, maybe up to 115 kBaud.
Thanks, I had a brief look at the standard - The protocol is quite slow. Why nobody at least let you type in the query, and only delay the search at startup is a mistery. Blocking the entry routine because the resource to be searched is not yet available, is not less than optimal. Regards Anton Erasmus