PSX-IGR is a combo-triggered reset mod for the PlayStation 1, enhancing reset control with controller-safe logic and LED feedback.
Originally based on the PlayStation 1 Reset Mod (2019), this version introduces improved input handling as timed combo-triggered reset, and responsive LED support, while being fully optimized for the PIC16F18325/26.
- How It Works
- Configurable Timing Parameters
- Building & Flashing
- PIC16F18325/26 Pinout
- LED Wiring Options
- ✅ Combo hold logic to prevent unintentional resets
- ✅ Combo feedback LED driven by asynchronous timer interrupt
- ✅ Reset feedback LED blink handled via the same non-blocking mechanism
- ✅ Support for PSU-mounted common-anode dual LED (RA5 control only)
- ✅ Optional support for 2-pin bicolor LED between RA4 and RA5 (dual-color feedback)
- ✅ Safe reset duration with post-reset lockout period
- ✅ Controller and GunCon combo support (based on ID)
- ✅ Behavior and timings fully configurable via
#definemacros
- Monitors SPI communication from the controller port.
- When a valid controller ID is detected, combo inputs are checked:
- Select + Start + L2 + R2 (standard controller)
- A + Trigger + B (GunCon)
- Select + X + L2 + R2 (XStation combo)
- A combo must be held for
COMBO_HOLDms to trigger a reset. - Reset is held for
SHORT_DELAYorLONG_DELAYdepending on combo. - During reset, the LED provides visual feedback with
RESET_BLINK_COUNTblinks. - After reset, a lockout period (
REBOOT_DELAY) ensures safe recovery before new inputs are accepted.
You can modify these constants in main.c to adjust behavior:
#define COMBO_HOLD 1250 // ms - Time combo must be held to trigger reset
#define RESET_BLINK_COUNT 3 // Number of blink cycles after reset
#define RESET_BLINK_TOTAL_MS 500 // ms - Total blink duration
#define RESET_BLINK_DELAY_MS 200 // ms - Delay after blink before returning to idleTo build from source:
- Use MPLAB X IDE and XC8 Compiler
- Target microcontroller: PIC16F18325 or PIC16F18326
- Set
__CONFIGfuses appropriately for:- Internal 32 MHz oscillator
- MCLR enabled
- Flash using ICSP with PICKit 3 or newer
For convenience, a precompiled .hex file is included in the Releases section.
This allows quick flashing using:
- MPLAB IPE 6.20 or newer
- PICKit 3 or compatible programmer
No source compilation is required if using the .hex.
| Pin | Name | Function |
|---|---|---|
| 1 | VCC | +3.3V |
| 2 | RA5 | COMBO/RESET - PRIMARY LED → Sinking control [-] for PSU 3-pin bicolor LED |
| 3 | RA4 | COMBO/RESET - AUXILIARY LED → For 2-pin bicolor LED |
| 4 | RA3 | ICSP MCLR/VPP |
| 5 | RC5 | RESET |
| 6 | RC4 | (not used) |
| 7 | RC3 | DEBUG |
| 8 | RC2 | SPI CMD |
| 9 | RC1 | SPI DATA |
| 10 | RC0 | SPI CLK |
| 11 | RA2 | SPI SS |
| 12 | RA1 | ICSP CLK |
| 13 | RA0 | ICSP DAT |
| 14 | VSS | GND |
Important
Using a feedback LED is optional. However, if you choose to use one, the following rules must be followed to ensure correct function and proper brightness.
- Drives the LED during combo detection and reset blink.
- RA5 is used either alone or together with RA4.
- Compatible with:
- 🟢🔴 3-pin common-anode LED: Connect 🔴 red cathode to RA5 via a 470 Ω resistor.
- 🟡 Single LED: Anode to VCC, cathode to RA5 via a 100-470 Ω resistor.
- Used only when connecting a 2-pin bicolor (antiparallel) LED between RA4 and RA5.
- Provides idle indication and supports dual-color feedback.
- Not intended for 3-pin common-anode LED or single LED use.
Note
If you're using a 3-pin common-anode LED, the green cathode resistor inside the PSU is usually 120-130 Ω.
To balance green brightness with RA5's red output, replace this resistor with 1.8 kΩ.
- Connect between RA4 and RA5 using a single 100 Ω resistor in series with either pin (no GND or VCC required).
- Provides dual-color feedback:
- 🟢 Green during idle
- 🔴 Red during combo
- 🔴⚫ Red blink during reset
- ⚫ OFF during post-reset delay
| System State | RA4 (pin 3) 🟢 |
RA5 (pin 2) 🔴 |
2-Pin Bicolor LED (antiparallel) 🟢🔴 |
Single Red LED or 3-Pin Red Terminal 🔴 |
|---|---|---|---|---|
| Idle | LO | HI | 🟢 Green (RA5 short pin) | ⚫ OFF |
| Combo detected | HI | LO | 🔴 Red | 🔴 ON |
| Reset (triggered) | HI | LO/HI toggle | 🔴⚫ Red Blinking | 🔴⚫ Red Blinking |
| Post-reset delay | Hi-Z | Hi-Z | ⚫ OFF | ⚫ OFF |
Warning
- RA4 is intended to work in push-pull with RA5 for 2-pin bicolor (antiparallel) LEDs.
- RA4 provides idle indication but stays constant during reset. Only RA5 blinks.
- RA4 provides only partial indication, and its use in combination with VCC or GND is not recommended.
⚠️ Always use at least one 100 Ω resistor in series with the LED to prevent hardware damage.
❓ Expected LED behavior when only RA4 is used for LED - Click to expand
| LED Type | Other Leg Connected To | Idle | Combo Detected | Reset (triggered) |
|---|---|---|---|---|
| 2-Pin Bicolor (1) | GND | ⚫ OFF | 🔴 Red | ⚫ OFF |
| 2-Pin Bicolor (1) | VCC | 🟢 Green | ⚫ OFF | ⚫ OFF |
| 2-Pin Bicolor (2) | GND | ⚫ OFF | 🟢 Green | ⚫ OFF |
| 2-Pin Bicolor (2) | VCC | 🔴 Red | ⚫ OFF | ⚫ OFF |
| Single LED (A) | GND | ⚫ OFF | 🟡 ON | ⚫ OFF |
| Single LED (A) | VCC | ⚫ OFF | ⚫ OFF | ⚫ OFF |
| Single LED (K) | GND | ⚫ OFF | ⚫ OFF | ⚫ OFF |
| Single LED (K) | VCC | 🟡 ON | ⚫ OFF | ⚫ OFF |
💡 Note: 2-pin bicolor LEDs long pin is usually marked as “1”
- 🔴 RA5 is the primary output for LED signaling, handling both combo detection and reset blink.
- 🟢 RA4 acts as a secondary output and only contributes when using a 2-pin bicolor (antiparallel) LED connected between RA4 and RA5.
- 🟡 For single LEDs, connect the anode (A) to VCC and the cathode (K) to RA5 via a 100-470 Ω resistor.
Example wiring for a 3-pin common-anode LED (Red/Green) - Click to expand
- 🟢 Green cathode (K) is connected to the PSU K line via a 1.8k Ω resistor
- This replaces the original PSU 130 Ω resistor to balance brightness
- The green side remains always on when the system is powered
- 🔘 Anode (A) is connected to the PSU A line (VCC)
- This is the common anode shared by both LED colors
- 🔴 Red cathode (K) is connected to RA5 (pin 2) of the PIC via a 470 Ω resistor
- Only RA5 (red cathode) is used for signaling (combo detection and reset blink)
- 🟠 All feedback signaling will appear orange, since the green side remains always on
This is a derivative work licensed under the Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0).
Modified and extended by Electroanalog® VICE (2025)
Based on PlayStation 1 Reset Mod by pyroesp (2019)
PlayStation is a registered trademark of Sony Interactive Entertainment LLC (SIE), formerly Sony Computer Entertainment Inc. (SCE). All rights reserved.
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