[Sprint HTC EVO 4G LTE] gunfromsako:
Hi EPST and reprogramming your phone, a comprehensive guide

I see a lot of posts in dev threads like "i flashed your rom now my signal/data is gone" so i decided to create this guide to help relieve unnecessary posts. Hope it helps :cowboy:

An introduction to EPST

Epst is a application that sprint uses to activate/program a phone. It read/writes to the NAM of your phone.NAM is an acronym for Numeric Assignment Module and is the place in TDMA/CDMA equipment where your phone number, ESN, system information and data settings live. In the old days we programmed handsets by hand, now it is usually done OTA (much is preset, a little is manually entered, data provisioning is truly OTA). It has many uses but this guide will concentrate on the data portion of epst. Here are the 3 codes that we will be using:

##3282# (data)

##72786# (scrtn)

##786# (reverse logistics support)

Keep in mind you will need your msl either from sprint (its really easy to get), or msl reader from the maket (root required)

##3282# (Data)

The Data menu is broken down into 6 menus and usb charging selection.

1. Data Profile: This is where you can setup multiple data profiles (not sure why you would to) and contains your sprint username and other info on your data profile.

2. Evdo: Two menus here DDTM and preferred mode. DDTM is an option to where if you are downloading over your 3g/1x it will send calls to voice mail. It can be useful if you are trying to download a large file over 3g and don't want it to be interrupted. Preferred mode is exactly that... your network preferred mode. There are several settings there all of which are safe to use. Mine is set to cdma hdr only because i have no lte in my area. In theory it should save a little battery life by not scanning for lte.

3. Advanced: This menu contains a lot of important info. From your esn/meid to toggling lte.

There a few settings in here you can tweak to possibly benefit from.

A. Slot Cycle Index (SCI): This determines how often a handset polls the network for coverage and incoming packets. The default value is 2. A "Slot" is 1.28 seconds and doubles with each incremental change from 0 to 7 (0=1.28, 1=2.56, 2=5.12 seconds, etc). setting a handset to poll more often may use noticeably more battery if coverage is thin or lacking.

B. ACCOLC (Access Overload Class): This code determines your priority to make and receive calls on the network. Higher the number, lower the priority. Lower the number, higher the priority. Emergency Services reserves 0 + 1 (please do not use these) leaving your choices to 2-9.

C.Removing the Sprint Proxy

1. With MSL in hand, go to the Phone app and dial ##3282#

2. Click Edit Mode

3. Your "Password" is your Phone's MSL, enter it here.

4. Click Advanced

5. Scroll down to RTSP/HTTP Setting

6. Change RTSP proxy IP to 0.0.0.0 or You can leave this blank if you like

7. Change RTSP proxy Port to 0 (Zero)

8. HTTP proxy IP to 0.0.0.0 or You could leave this blank if you like

9. HTTP proxy port to 0 (Zero)

10.Once complete, back out to the home screen and enjoy Downloads and a .20- .60 mbps increase in 3G speeds!

It may not hurt to verify the settings are in place by following steps 1 through 5 again, if you're OCD. Removing this proxy removes at least one or more hops in between you and your connection destination, possibly increasing your WAN connection speed via 2G/3G/4G and Wi-Fi. As always, use at your own risk and take a screen shot of your original settings.

D. Improve CDMA Call Sound Quality via a Codec Change:

There are a few important things to note. This adjustment changes the Codec used to compress the voices of you and your caller across the Cell Network using EVRC-B which is an updated revision to the current CDMA standard EVRC. It has been noted in a few places, that making this change CAN effect your ability to make outbound calls in some roaming situations, including over Network extenders like the AirRave. As always, YMMV and I STRONGLY recommend that you both test this change in your normal use environments as well as keep a general idea of these instructions handy in the event you need to revert to the default settings in an emergency. As always, YOU and YOU ALONE are FULLY responsible for changes to any handset in which these and any modifications are made.

1. With MSL in hand, go to the Phone app and dial ##3282#

2. Click Edit Mode

3. Your "Password" is your Phone's MSL, enter it here.

4. Click Advanced

5. Scroll down the list and note the entries for EVRC-B, Home Orig, and Roam Orig.

6. Change EVRC-B to "Enable"

7. Change Home Orig and Roam Orig to "EVRC-B"

8. Hit Menu, and select "Commit Modifications"

9. Your phone will prompt you to click ok to restart or it will restart automatically.

To reverse the changes, repeat all of the above steps except change the following.

6. Change EVRC-B to "Disable"

7. Change Home Orig and Roam Orig to "EVRC"

Click to learn more about EVRC and EVRC-B​

4. DSS:Not sure if these really need to be messed with unless you have flashed to another carrier...

5. LTE Record Various logs and scan rates for LTE safe to adjust...

6. PDN Setting I only found one document which seemed to pertain to this Here There are 3 sub menus internet, ota, and pam (phone as modem?). If anyone knows more about this fell free to chime in. :good:

##72786# (SCTRN)

This menu contains 4 sections containing your MDN, MSID, M.IP Custom Profile1-NAI and AAA shared secret password. All of these are unique to your data profile and should never change. The ##code is used to reset these 4 items to re-provision your phone without wiping any data.

##786# (Hard Reset)

This menu contains a lot of the same info as the previous codes with a little extra. It is used for the quintessential "hard reset". This will completely wipe data/app, your internal sd, and NAM so your phone can be re-provisioned.

FAQ SECTION

Note: I do not fully understand how or why the NAM section of your phone becomes corrupt but is does. I have never had to call sprint to have them fix my data so i hope this helps.

Q. Help im stuck on 1x/2g.

Q. I just flashed your rom now i have no signal help!

Q. My data speeds really suck lately anyone else?

Note: All these fixes must be preformed on a stock or stock based rom with epst support and make sure you are in a known good signal area

A. These are all very common questions i have seen around here in the past years and are all very easy to fix... process below.

Whenever i have data issues whether it be stuck on 1x, no data/signal, or slow data, I always follow the following steps...

1. ill just do a profile update and see if that helps.

2. If that doesn't help this is my next step.

Enter Dialer

##3282#

select edit and enter MSL

select data profile

select menu and select Restore

reboot and update profile

3.Still no worky?

Enter Dialer:

##72786#

select edit and enter MSL

select menu and then Reset

After phone goes through "hands free activation" and your back at your dialer, enter this:

##3282#

select edit and enter MSL

select data profile

select menu and select Restore

After your rebooted and back at your home screen go into settings/system updates/ and update your profile.

4. This is your last step before calling sprint (which i have never had to, this has always worked for me).

THIS WILL WIPE EVERYTHING IN DATA/APP AS WELL AS YOUR INTERNAL SD! YOU HAVE BEEN WARNED SO MAKE A BACKUP

Enter Dialer

##786#

select menu and select reset

enter msl and select ok

After phone goes through "hands free activation" go into settings/system updates/ and update your profile and you should be set​

This guide is a WIP, and yes i know most of this information is already in some thread buried somewhere but I thought a little consolidation was in order. Maybe we can get data questions in here and there wont be 4 pages of someone trying to figure out why their data wont work in a dev thread.:cowboy::good:

Also this is my first attempt at a guide...go easy on me.