ppp-modem: reset pulse is too short on A7672G

[tl-sl]

Board

Custom Esp32

Device Description

Simcom A7672G

Hardware Configuration

not relevant

Version

v3.0.1

IDE Name

PlatformIO

Operating System

Linux

Flash frequency

40Mhz

PSRAM enabled

no

Upload speed

115200

Description

Testing ppp-modem on Simcom A7672 using the SIM7600 driver. Reset pulse of 200ms does not trigger reset of the modem.

A7672 datasheet says reset pulse should be 2.5secs, and in my testing anything under 2secs fails to reset.

Looking at other datasheets the pulse time for reset varies significantly across different simcom models, perhaps this value could be made configurable? If so can make a PR for this issue.

Sketch

from ppp library

    perimanSetPinBusExtraType(_pin_rst, "PPP_MODEM_RST");
    digitalWrite(_pin_rst, !_pin_rst_act_low);
    delay(200);
    digitalWrite(_pin_rst, _pin_rst_act_low);
    delay(100);

### Debug Message

```plain
[103772][E][PPP.cpp:311] begin(): Failed to wait for communication

Other Steps to Reproduce

any reset pulse under 2000ms will fail to reset device ending with the above debug message.

I have checked existing issues, online documentation and the Troubleshooting Guide

• I confirm I have checked existing issues, online documentation and Troubleshooting guide.

[me-no-dev]

If so can make a PR for this issue.

Please do 😄