wiki.js/boards/Dropbear.md

---
title: Dropbear
description: 
published: true
date: 2020-12-28T00:43:31.031Z
tags: 
editor: markdown
dateCreated: 2020-12-24T00:42:27.964Z
---

# Dropbear ECU
The Dropbear is an 8 fuel + 8 ignition ECU that is currently in testing prior to a full production release. It is powered by the high speed Teensy 3.5 board and is designed to be a complete unit out of the box. 

## Features

- 8x high impedance injector drivers
- 8x 5v/12v coil pre-drivers (For use with igniters/smart coils)
- 6x medium current (2A) outputs
- 7x analog inputs
- 4x digital inputs
- CAN transceiver
- Onboard VR conditioner
- Swappable internal MAP sensors
- Onboard baro sensor
- Optional stepper motor driver


## Pin out
### Black Connector      
![Connector_black.png](/img/boards/Connector_black.png){.align-center width=400}

| Pin | Direction | Max Current | Purpose | Comment |
|-----|-----------|-------------|---------|---------|
| A1  | Input     | 5A          | Switched 12v      | Main power input. Connect to switched 12v power via 5A fuse        |
| A2  | Input     | 15A         | Power Ground      | Connect to battery negative.        |
| A3  | Output    | 80mA        | Sensor reference  | Used for sensors requiring a 5v reference (Eg TPS). **Do not use for powering offboard systems.**        |
| A4  | N/A       | N/A         | Not used.         |         |
| A5  | Input     | N/A         | Spare Digital In 2| 12v or Ground switching digital input. Can be used for VSS, Idle Up etc        |
| A6  | Both      | N/A         | CAN L             | CAN L connection        |
| A7  | Both      | N/A         | CAN H             | CAN H connection        |
| A8  | Input     | 15A         | Power Ground      | Connect to battery negative.        |
| B1  | Output    | 100mA       | Tacho             | 12v square wave output for use as input to a tachometer        |
| B2  | Input     | N/A         | Crank Primary     | Primary crank sensor (CKP) input. Can be 12v, Ground switching or the positive wire of a Vr sensor. See 'Crank/Cam' section below        |
| B3  | Input     | N/A         | Crank Negative    | **Only used with a VR sensor.** Connect to negative side of VR crank sensor. See 'Crank/Cam' section below        |
| B4  | Input     | N/A         | Cam Primary     | Primary crank sensor (CKP) input. Can be 12v, Ground switching or the positive wire of a Vr sensor. See 'Crank/Cam' section below        |
| B5  | Input     | N/A         | Cam Negative    | **Only used with a VR sensor.** Connect to negative side of VR cam sensor. See 'Crank/Cam' section below        |
| B6  | Input     | N/A         | Spare Digital 1| 12v or Ground switching digital input. Can be used for VSS, Idle Up etc        |
| B7  | Input     | N/A         | Clutch input.     | Ground switching digital input that goes to ground when clutch is engaged. Do not feed 12v on this input        |
| B8  | Input     | N/A         | Flex sensor       | Signal wire from GM/Continental Flex sensor.         |
| C1  | Output    | N/A         | Analog ground     | Ground reference for use by sensors such as TPS, IAT, CLT. **Do not use for powering offboard controllers**       |
| C2  | Input     | N/A         | Spare Analog 1    | Spare analog input for use with sensors such as fuel pressure/temperature, oil pressure etc. Should be a 0-5v signal        |
| C3  | Input     | N/A         | Spare Analog 2    | Spare analog input for use with sensors such as fuel pressure/temperature, oil pressure etc. Should be a 0-5v signal        |
| C4  | Input     | N/A         | O2 Sensor         | Connect to the 0-5v signal wire of external wideband controller. Can also be used with 0-1v output from narrowband sensor however wideband is **strongly** recommended        |
| C5  | Input     | N/A         | Coolant Sensor    | Connect to one side of 2 wire coolant sensor (CLT). Other side of sensor connected to pin C1        |
| C6  | Input     | N/A         | Inlet Air Sensor  | Connect to one side of 2 wire inlet air temp sensor (IAT). Other side of sensor connected to pin C1        |
| C7  | Input     | N/A         | Throttle Sensor   | Connect to signal line of variable throttle position sensor (TPS). Other pins of sensor should connect to C1 and A3        |
| C8  | Input     | N/A         |External MAP Sensor| Signal line if using external MAP sensor. Input should be 0-5v and MAP source switch should be set to 'Ext.'. See below for 'Switch Configuration'. If using internal sensor this pin should be left unconnected.        |

### Grey Connector
![Connector_black.png](/img/boards/Connector_grey.png){.align-center width=400}

| Pin | Direction | Max Current | Purpose | Comment |
|-----|-----------|-------------|---------|---------|
| A1  | Output    | 2A          | Injector 1        | Injector 1 output        |
| A2  | Output    | 2A          | Injector 2        | Injector 2 output        |
| A3  | Output    | 2A          | Injector 3        | Injector 3 output        |
| A4  | Output    | 2A          | Injector 4        | Injector 4 output        |
| A5  | Output    | 2A          | Injector 5        | Injector 5 output        |
| A6  | Output    | 2A          | Injector 6        | Injector 6 output        |
| A7  | Output    | 2A          | Injector 7        | Injector 7 output        |
| A8  | Output    | 2A          | Injector 8        | Injector 8 output        |
| B1  | Output    | 100mA       | Ignition 1        | Ignition 1 outout. 5v or 12v depending on switch selection. **Do not connect directly to high current coils**, only connect to igniter or 'smart' coil        |
| B2  | Output    | 100mA       | Ignition 2        | Ignition 2 outout. 5v or 12v depending on switch selection. **Do not connect directly to high current coils**, only connect to igniter or 'smart' coil        |
| B3  | Output    | 100mA       | Ignition 3        | Ignition 3 outout. 5v or 12v depending on switch selection. **Do not connect directly to high current coils**, only connect to igniter or 'smart' coil        |
| B4  | Output    | 100mA       | Ignition 4        | Ignition 4 outout. 5v or 12v depending on switch selection. **Do not connect directly to high current coils**, only connect to igniter or 'smart' coil        |
| B5  | Output    | 100mA       | Ignition 5        | Ignition 5 outout. 5v or 12v depending on switch selection. **Do not connect directly to high current coils**, only connect to igniter or 'smart' coil        |
| B6  | Output    | 100mA       | Ignition 6        | Ignition 6 outout. 5v or 12v depending on switch selection. **Do not connect directly to high current coils**, only connect to igniter or 'smart' coil        |
| B7  | Output    | 100mA       | Ignition 7        | Ignition 7 outout. 5v or 12v depending on switch selection. **Do not connect directly to high current coils**, only connect to igniter or 'smart' coil        |
| B8  | Output    | 100mA       | Ignition 8        | Ignition 8 outout. 5v or 12v depending on switch selection. **Do not connect directly to high current coils**, only connect to igniter or 'smart' coil        |
| C1  | Output    | 2A          | Boost             | Ground switching output for use with boost control solenoid        |
| C2  | Output    | 2A          | Fan.              | Ground switching output for triggering a fan relay. **Do not drive fan directly from this pin, use only with relay**        |
| C3  | Output    | 2A          | Spare 2/Stepper-B2  | Can be used either as ground switching output for general purpose use or 12v output if using a stepper idle control (Requires stepper driver to be fitted, see below)       |
| C4  | Output    | 2A          | Idle/Stepper-B1  | Can be used either as ground switching idle output (For use with PWM valves) or 12v output if using a stepper idle control (Requires stepper driver to be fitted, see below)       |
| C5  | Output    | 2A          | VVT/Stepper-A1.   | Can be used either as ground switching VVT output or 12v output if using a stepper idle control (Requires stepper driver to be fitted, see below)       |
| C6  | Output    | 2A          | Spare 1/Stepper-A2  | Can be used either as ground switching output for general purpose use or 12v output if using a stepper idle control (Requires stepper driver to be fitted, see below)       |
| C7  | Output    | 1.5A        | Fuel Pump         | Ground switching output for triggering fuel pump relay. **Do not drive pump directly from this pin, use only with relay**        |
| C8  | Input     | 15A         | Power Ground      | Connect to battery negative.        |

## Board Configuration
The Dropbear board contains 4 switches and 1 DIP switch pair that can be used to change the setup of the ECU. 

### VR Conditioner
The ECU contains a dual onboard conditioner that can can be used with VR sensors. 

### MAP Selector
The Dropbear board uses a removable MAP card containing the sensor and a short hose running to the bulkhead connector on the enclosure. Currently only the default 0-250kpa sensor board is available, with higher range boards to be made available in the future. To use this MAP card, select the `Int.` (Internal) option on the MAP switch. 

If you wish to use an external MAP sensor located in the engine bay, this switch should be to to `Ext.` and the sensors signal line should be connected to pin `C8` on the Black connector. The MAP card can be left in place or removed when the `Ext.` option is used.
docs: create boards/Dropbear 2020-12-23 16:42:39 -08:00			`---`
			`title: Dropbear`
			`description:`
			`published: true`
docs: update boards/Dropbear 2020-12-27 16:43:40 -08:00			`date: 2020-12-28T00:43:31.031Z`
docs: create boards/Dropbear 2020-12-23 16:42:39 -08:00			`tags:`
			`editor: markdown`
			`dateCreated: 2020-12-24T00:42:27.964Z`
			`---`

docs: update boards/Dropbear 2020-12-26 15:37:29 -08:00			`# Dropbear ECU`
			`The Dropbear is an 8 fuel + 8 ignition ECU that is currently in testing prior to a full production release. It is powered by the high speed Teensy 3.5 board and is designed to be a complete unit out of the box.`
docs: create boards/Dropbear 2020-12-23 16:42:39 -08:00
docs: update boards/Dropbear 2020-12-26 15:37:29 -08:00			`## Features`

			`- 8x high impedance injector drivers`
			`- 8x 5v/12v coil pre-drivers (For use with igniters/smart coils)`
			`- 6x medium current (2A) outputs`
			`- 7x analog inputs`
			`- 4x digital inputs`
			`- CAN transceiver`
			`- Onboard VR conditioner`
			`- Swappable internal MAP sensors`
			`- Onboard baro sensor`
			`- Optional stepper motor driver`


			`## Pin out`
			`### Black Connector`
docs: update boards/Dropbear 2020-12-23 18:00:10 -08:00			`![Connector_black.png](/img/boards/Connector_black.png){.align-center width=400}`
docs: create boards/Dropbear 2020-12-23 16:42:39 -08:00
			`\| Pin \| Direction \| Max Current \| Purpose \| Comment \|`
			`\|-----\|-----------\|-------------\|---------\|---------\|`
			`\| A1 \| Input \| 5A \| Switched 12v \| Main power input. Connect to switched 12v power via 5A fuse \|`
			`\| A2 \| Input \| 15A \| Power Ground \| Connect to battery negative. \|`
			`\| A3 \| Output \| 80mA \| Sensor reference \| Used for sensors requiring a 5v reference (Eg TPS). Do not use for powering offboard systems. \|`
			`\| A4 \| N/A \| N/A \| Not used. \| \|`
			`\| A5 \| Input \| N/A \| Spare Digital In 2\| 12v or Ground switching digital input. Can be used for VSS, Idle Up etc \|`
			`\| A6 \| Both \| N/A \| CAN L \| CAN L connection \|`
			`\| A7 \| Both \| N/A \| CAN H \| CAN H connection \|`
			`\| A8 \| Input \| 15A \| Power Ground \| Connect to battery negative. \|`
			`\| B1 \| Output \| 100mA \| Tacho \| 12v square wave output for use as input to a tachometer \|`
			`\| B2 \| Input \| N/A \| Crank Primary \| Primary crank sensor (CKP) input. Can be 12v, Ground switching or the positive wire of a Vr sensor. See 'Crank/Cam' section below \|`
			`\| B3 \| Input \| N/A \| Crank Negative \| Only used with a VR sensor. Connect to negative side of VR crank sensor. See 'Crank/Cam' section below \|`
			`\| B4 \| Input \| N/A \| Cam Primary \| Primary crank sensor (CKP) input. Can be 12v, Ground switching or the positive wire of a Vr sensor. See 'Crank/Cam' section below \|`
			`\| B5 \| Input \| N/A \| Cam Negative \| Only used with a VR sensor. Connect to negative side of VR cam sensor. See 'Crank/Cam' section below \|`
			`\| B6 \| Input \| N/A \| Spare Digital 1\| 12v or Ground switching digital input. Can be used for VSS, Idle Up etc \|`
			`\| B7 \| Input \| N/A \| Clutch input. \| Ground switching digital input that goes to ground when clutch is engaged. Do not feed 12v on this input \|`
			`\| B8 \| Input \| N/A \| Flex sensor \| Signal wire from GM/Continental Flex sensor. \|`
			`\| C1 \| Output \| N/A \| Analog ground \| Ground reference for use by sensors such as TPS, IAT, CLT. Do not use for powering offboard controllers \|`
			`\| C2 \| Input \| N/A \| Spare Analog 1 \| Spare analog input for use with sensors such as fuel pressure/temperature, oil pressure etc. Should be a 0-5v signal \|`
			`\| C3 \| Input \| N/A \| Spare Analog 2 \| Spare analog input for use with sensors such as fuel pressure/temperature, oil pressure etc. Should be a 0-5v signal \|`
			`\| C4 \| Input \| N/A \| O2 Sensor \| Connect to the 0-5v signal wire of external wideband controller. Can also be used with 0-1v output from narrowband sensor however wideband is strongly recommended \|`
			`\| C5 \| Input \| N/A \| Coolant Sensor \| Connect to one side of 2 wire coolant sensor (CLT). Other side of sensor connected to pin C1 \|`
			`\| C6 \| Input \| N/A \| Inlet Air Sensor \| Connect to one side of 2 wire inlet air temp sensor (IAT). Other side of sensor connected to pin C1 \|`
			`\| C7 \| Input \| N/A \| Throttle Sensor \| Connect to signal line of variable throttle position sensor (TPS). Other pins of sensor should connect to C1 and A3 \|`
			`\| C8 \| Input \| N/A \|External MAP Sensor\| Signal line if using external MAP sensor. Input should be 0-5v and MAP source switch should be set to 'Ext.'. See below for 'Switch Configuration'. If using internal sensor this pin should be left unconnected. \|`

docs: update boards/Dropbear 2020-12-26 15:37:29 -08:00			`### Grey Connector`
docs: update boards/Dropbear 2020-12-23 18:00:10 -08:00			`![Connector_black.png](/img/boards/Connector_grey.png){.align-center width=400}`

docs: create boards/Dropbear 2020-12-23 16:42:39 -08:00			`\| Pin \| Direction \| Max Current \| Purpose \| Comment \|`
			`\|-----\|-----------\|-------------\|---------\|---------\|`
			`\| A1 \| Output \| 2A \| Injector 1 \| Injector 1 output \|`
			`\| A2 \| Output \| 2A \| Injector 2 \| Injector 2 output \|`
			`\| A3 \| Output \| 2A \| Injector 3 \| Injector 3 output \|`
			`\| A4 \| Output \| 2A \| Injector 4 \| Injector 4 output \|`
			`\| A5 \| Output \| 2A \| Injector 5 \| Injector 5 output \|`
			`\| A6 \| Output \| 2A \| Injector 6 \| Injector 6 output \|`
			`\| A7 \| Output \| 2A \| Injector 7 \| Injector 7 output \|`
			`\| A8 \| Output \| 2A \| Injector 8 \| Injector 8 output \|`
			`\| B1 \| Output \| 100mA \| Ignition 1 \| Ignition 1 outout. 5v or 12v depending on switch selection. Do not connect directly to high current coils, only connect to igniter or 'smart' coil \|`
			`\| B2 \| Output \| 100mA \| Ignition 2 \| Ignition 2 outout. 5v or 12v depending on switch selection. Do not connect directly to high current coils, only connect to igniter or 'smart' coil \|`
			`\| B3 \| Output \| 100mA \| Ignition 3 \| Ignition 3 outout. 5v or 12v depending on switch selection. Do not connect directly to high current coils, only connect to igniter or 'smart' coil \|`
			`\| B4 \| Output \| 100mA \| Ignition 4 \| Ignition 4 outout. 5v or 12v depending on switch selection. Do not connect directly to high current coils, only connect to igniter or 'smart' coil \|`
			`\| B5 \| Output \| 100mA \| Ignition 5 \| Ignition 5 outout. 5v or 12v depending on switch selection. Do not connect directly to high current coils, only connect to igniter or 'smart' coil \|`
			`\| B6 \| Output \| 100mA \| Ignition 6 \| Ignition 6 outout. 5v or 12v depending on switch selection. Do not connect directly to high current coils, only connect to igniter or 'smart' coil \|`
			`\| B7 \| Output \| 100mA \| Ignition 7 \| Ignition 7 outout. 5v or 12v depending on switch selection. Do not connect directly to high current coils, only connect to igniter or 'smart' coil \|`
			`\| B8 \| Output \| 100mA \| Ignition 8 \| Ignition 8 outout. 5v or 12v depending on switch selection. Do not connect directly to high current coils, only connect to igniter or 'smart' coil \|`
			`\| C1 \| Output \| 2A \| Boost \| Ground switching output for use with boost control solenoid \|`
			`\| C2 \| Output \| 2A \| Fan. \| Ground switching output for triggering a fan relay. Do not drive fan directly from this pin, use only with relay \|`
			`\| C3 \| Output \| 2A \| Spare 2/Stepper-B2 \| Can be used either as ground switching output for general purpose use or 12v output if using a stepper idle control (Requires stepper driver to be fitted, see below) \|`
			`\| C4 \| Output \| 2A \| Idle/Stepper-B1 \| Can be used either as ground switching idle output (For use with PWM valves) or 12v output if using a stepper idle control (Requires stepper driver to be fitted, see below) \|`
			`\| C5 \| Output \| 2A \| VVT/Stepper-A1. \| Can be used either as ground switching VVT output or 12v output if using a stepper idle control (Requires stepper driver to be fitted, see below) \|`
			`\| C6 \| Output \| 2A \| Spare 1/Stepper-A2 \| Can be used either as ground switching output for general purpose use or 12v output if using a stepper idle control (Requires stepper driver to be fitted, see below) \|`
			`\| C7 \| Output \| 1.5A \| Fuel Pump \| Ground switching output for triggering fuel pump relay. Do not drive pump directly from this pin, use only with relay \|`
docs: update boards/Dropbear 2020-12-27 16:43:40 -08:00			`\| C8 \| Input \| 15A \| Power Ground \| Connect to battery negative. \|`

			`## Board Configuration`
			`The Dropbear board contains 4 switches and 1 DIP switch pair that can be used to change the setup of the ECU.`

			`### VR Conditioner`
			`The ECU contains a dual onboard conditioner that can can be used with VR sensors.`

			`### MAP Selector`
			The Dropbear board uses a removable MAP card containing the sensor and a short hose running to the bulkhead connector on the enclosure. Currently only the default 0-250kpa sensor board is available, with higher range boards to be made available in the future. To use this MAP card, select the `Int.` (Internal) option on the MAP switch.

			If you wish to use an external MAP sensor located in the engine bay, this switch should be to to `Ext.` and the sensors signal line should be connected to pin `C8` on the Black connector. The MAP card can be left in place or removed when the `Ext.` option is used.