# What is xbee s2c 802.15.4 ADC range **URL:** \ **Category:** XBee - 802.15.4\ **Tags:** adc, adc-range\ **Created:** [September 6, 2022, 8:34am UTC](https://forums.digi.com/t/what-is-xbee-s2c-802-15-4-adc-range/23221 "2022-09-06T08:34:02Z")\ **Posts on this page:** 6\ **Page:** 1
**Author:** ![bastien](https://avatars.discourse-cdn.com/v4/letter/b/51bf81/32.png) [@bastien](https://forums.digi.com/u/bastien)\ **Post date:** [September 6, 2022, 8:34am UTC](https://forums.digi.com/t/what-is-xbee-s2c-802-15-4-adc-range/23221/1 "2022-09-06T08:34:02Z")
Hi I have xbees s2c 802.15.4 (XB24CAPIT-001) I have now issues reading ADC, and I suspect that the range I assumed (0 to 3.3V) is actually less (1.2V ?) I have been looking at the doc and I have found: - The user manual that says nothing but “Vref Feature not supported on this device” There is nothing I found about the ADC range in that doc… unfortunately - questions on this very forum such as : [https://forums.digi.com/4660/what-is-the-maximum-analog-input-voltage](https://forums.digi.com/4660/what-is-the-maximum-analog-input-voltage) which is not clear for me, because I do not get the logic of xbee modules naming. Is the s2c a serie 1, 2 3 ? Is zigbee or ZB equivalent to a serie in particular ? - [https://www.digi.com/resources/documentation/Digidocs/90002002/Reference/r\_zb\_i\_o\_sampling.htm](https://www.digi.com/resources/documentation/Digidocs/90002002/Reference/r_zb_i_o_sampling.htm) Which clearly says : “0x0000 represents 0 V, and 0x3FF = 1.2 V” But then again, does “XBee/XBee-PRO Zigbee RF Modules” apply to xbee s2c 802.15.4 (XB24CAPIT-001) ? - [https://www.digi.com/support/knowledge-base/digital-and-analog-sampling-using-xbee-radios](https://www.digi.com/support/knowledge-base/digital-and-analog-sampling-using-xbee-radios) Which states that 802.15.4 can use Vref (thought there’s a “\*” which I don’t find what it refers to), and that ZigBee only has 1.2V Vref fixed. Again I found the module naming confusing - [https://www.digi.com/resources/documentation/Digidocs/90000982/reference/r\_specs\_ele\_char\_802.htm?TocPath=Specifications|\_\_\_\_\_1](https://www.digi.com/resources/documentation/Digidocs/90000982/reference/r_specs_ele_char_802.htm?TocPath=Specifications%7C _____ 1) Which refers to XBee/XBee-PRO XBee/XBee-PRO S1 802.15.4 (Legacy) RF Module. What is legacy ? What is not ? - [https://www.digi.com/blog/post/xbee-buying-guide](https://www.digi.com/blog/post/xbee-buying-guide) Which did not make it more clear. Then again how do I map serial number and serie ? Could it be possible to get : - a clear chart on what serial number is what module type ? Along with all nicknames, that are found across doc + forum, such as legacy, serie X, ZB, etc ? - a clear chart on what module type support Vref, and if not what is the ADC range ? Thanks in advance for the answer I wish this would have been clearly written in the user manual, as it would have save manual rework on the prototype and need for a new PCB version If Digi people stumble upon that post, could that info be added to the next version of the manual ? ---
**Author:** ![plater](https://avatars.discourse-cdn.com/v4/letter/p/f05b48/32.png) [@plater](https://forums.digi.com/u/plater)\ **Post date:** [September 6, 2022, 10:53am UTC](https://forums.digi.com/t/what-is-xbee-s2c-802-15-4-adc-range/23221/2 "2022-09-06T10:53:52Z")
Page 183 of the datasheet has a mapping: [https://www.digi.com/resources/documentation/digidocs/pdfs/90001500.pdf](https://www.digi.com/resources/documentation/digidocs/pdfs/90001500.pdf) Model: S2CTH (XBee S2C through-hole) IFETEL (IFT) number RCPDIS219-1821-A1 applies to these S2C radios: XB24CAPIT-001, The max range is listed as 1.2v, I suspect the vREF pin on other models lets you supply your own voltage value, but that model is locked to 1.2v The (Legacy) models were from a design by maxstream before they were bought by digi. I don’t know how they relate to the S2C models. We skipped from the legacy up to the xb3 version. If I am not mistaken the Legacy parts are S1(series1) and yours are S2(series2), and the newer XB3s are the S3(series3)? ---
**Author:** ![bastien](https://avatars.discourse-cdn.com/v4/letter/b/51bf81/32.png) [@bastien](https://forums.digi.com/u/bastien)\ **Post date:** [September 6, 2022, 1:47pm UTC](https://forums.digi.com/t/what-is-xbee-s2c-802-15-4-adc-range/23221/3 "2022-09-06T13:47:24Z")
Thanks for the answer The model mapping is indeed at the end of the manual But what about the ADC max range being 1.2V ? Where did you find that ? The only time I found 1.2V was about ZigBee units. Is ZigBee an alias of XB24CAPIT-001 ? Or of S2C ? ---
**Author:** ![plater](https://avatars.discourse-cdn.com/v4/letter/p/f05b48/32.png) [@plater](https://forums.digi.com/u/plater)\ **Post date:** [September 6, 2022, 2:14pm UTC](https://forums.digi.com/t/what-is-xbee-s2c-802-15-4-adc-range/23221/4 "2022-09-06T14:14:36Z")
The datasheet i linked is for the XBee/XBee-PRO S2C 802.15.4 Page 70 “Analog input” says max adc value is 1.2v It would be nice if there was a modules section giving the electrical characteristics (like drive strength for pins) and etc, but it seems to be buried. ---
**Author:** ![bastien](https://avatars.discourse-cdn.com/v4/letter/b/51bf81/32.png) [@bastien](https://forums.digi.com/u/bastien)\ **Post date:** [September 7, 2022, 10:14am UTC](https://forums.digi.com/t/what-is-xbee-s2c-802-15-4-adc-range/23221/5 "2022-09-07T10:14:39Z")
haaaa… It was there ! Thanks About drive strength and such, what about “GPIO specifications” page 31 ? ---
**Author:** ![plater](https://avatars.discourse-cdn.com/v4/letter/p/f05b48/32.png) [@plater](https://forums.digi.com/u/plater)\ **Post date:** [September 7, 2022, 10:46am UTC](https://forums.digi.com/t/what-is-xbee-s2c-802-15-4-adc-range/23221/6 "2022-09-07T10:46:04Z")
I knew it was in there somewhere hah