ESP32 RST is inaccessible on H802/H803 when stacked on T-Sim Shield inside T-Solar

Hardware involved

• H802 — T-SIM7670G-S3 Standard
• H803 — T-SIM7600G-S3 Standard
• H783-01 — T-Sim Shield
• K267 — T-Solar enclosure/kit
• External 1S4P battery pack and the T-Solar panel
• Normal field operation has no USB cable connected

Problem

On both the H802 and H803 Standard mainboards, the ESP32 RST button is located on the bottom side of the PCB.

When either mainboard is installed on the H783-01 T-Sim Shield using the intended stacking connectors and the assembly is placed inside the K267 T-Solar enclosure, the RST button remains between the two boards. It cannot be pressed without removing/disassembling the mainboard from the Shield.

The T-Sim Shield also does not expose the ESP32 EN/CHIP_PU reset signal or provide an accessible MCU reset button. The documented SIMSHIELD_RADIO_RST signal is only for the SX1262 LoRa radio and does not reset the ESP32/mainboard.

This is a significant serviceability problem for unattended solar/battery installations. If the ESP32 must be manually reset during installation, testing, recovery, or field maintenance, the complete stack must be disassembled.

Steps to reproduce

1. Install an H802 T-SIM7670G-S3 Standard or H803 T-SIM7600G-S3 Standard on an H783-01 T-Sim Shield.
2. Mount the stack inside the K267 T-Solar enclosure.
3. Power the assembly from the external 1S4P battery and solar panel, without USB.
4. Try to press the ESP32 RST button.

Actual result: the button is physically inaccessible between the mainboard and the Shield.

Expected result: the ESP32 can be manually reset without disconnecting or disassembling the stacked boards.

Requested hardware improvement

Please consider either of these solutions for the next hardware revision:

1. Move the ESP32 RST button to the top/accessible side of the H802 and H803 Standard mainboards; or
2. Route ESP_EN / CHIP_PU and GND through the stacking connector and add an accessible reset button, pads, or header on the T-Sim Shield.

Ideally, the solution should work while the complete H802/H803 + H783-01 stack is installed inside the K267 T-Solar enclosure and powered only by the battery and solar panel.

Official references

• H802 documentation: https://github.com/Xinyuan-LILYGO/LilyGo-Modem-Series/blob/main/docs/en/esp32s3/sim7670g-s3-standard/README.MD#button-description
• H803 documentation: https://github.com/Xinyuan-LILYGO/LilyGo-Modem-Series/blob/main/docs/en/esp32s3/sim7600g-s3-standard/README.MD#button-description
• T-Sim Shield guide: https://github.com/Xinyuan-LILYGO/LilyGo-Modem-Series/blob/main/docs/en/SimshieldUsageGuide/README.md
• T-Sim Shield schematic: https://github.com/Xinyuan-LILYGO/LilyGo-Modem-Series/blob/main/schematic/shield/T-SimShield-Rev1.0.pdf

Thank you for considering this improvement. It would make the Standard-series boards much more suitable for unattended outdoor and solar-powered installations.