Automated Test Equipment Mainframe
This Automated Test Equipment (ATE) Mainframe is a prototype I built out of a repurposed Eurocard chassis. It was designed to accommodate up to eight ATE Modules, and uses a shared TTL-UART bus and an integrated USB-to-TTL serial interface to query, program and synchronise the various modules.
Design Considerations
- Support a shared inter-module control bus
 - Do so in a way which neither ties up all of the available intra-module SPI or I2C buses, nor makes the system vulnerable to inter-module conflicts or I2C device address contention
 - Ideally do so in a way that is compatible with ATmega 328P-based microcontroller boards (e.g. the Arduino Nano / Mini Pro)
 - Shared power and reset lines, and a backplane that automatically sets the unit IDs based upon slot position
 - A software-level command interface that allows individual modules to be addressed, but which also allows for 'group' or chassis-wide events such as triggers, etc.
 - Ideally uses a command interface / syntax which resembles existing / industry standards
 
Bus Pinouts
| Pin | Function | Pin | Function | 
|---|---|---|---|
| 1 (top) | +12V supply | 11 | (Reserved) | 
| 2 | 12 | (Reserved) | |
| 3 | +5V supply | 13 | (Reserved) | 
| 4 | 14 | (Reserved) | |
| 5 | GND | 15 | (Reserved) | 
| 6 | 16 | (Reserved) | |
| 7 | RxD (shared) | 17 | Address Select 0 | 
| 8 | TxD (shared) | 18 | Address Select 1 | 
| 9 | GND | 19 | Address Select 2 | 
| 10 | /RST | 20 | Address Select 3 | 
Compatible Modules
| Module | Model | Category | ↑ Description | 
|---|---|---|---|
| IOM-8-4 Basic I/O ATE Module | IOM-8-4 | ATE, I/O | Custom simple, multi-channel digital and analogue I/O module with an SCPI-like command interface | 
| DCL-100 Programmable DC Load Module | DCL-100 | ATE, Power | Custom simple 0 – 10A Programmable DC Load module with an SCPI-like command interface | 
| SGM-125-2 Tracking Generator ATE Module | SGM-125-2 | ATE, Signal Generator | Custom dual-channel 12.5MHz Signal Generator module with limited tracking functionality and an SCPI-like command interface | 
| ATE Eurocard Mainframe | ATE Eurocard Mainframe | ATE | Custom Mainframe supporting up to eight Eurocard-based ATE Modules and an integrated USB-to-TTL-UART multi-master control bus | 
- Category:
 - ATE
 - Entry:
 - ATE Eurocard Mainframe
 - Make:
 - Enginuity
 - Model:
 - ATE Eurocard Mainframe
 - Description:
 - Custom Mainframe supporting up to eight Eurocard-based ATE Modules and an integrated USB-to-TTL-UART multi-master control bus
 - Status:
 - Working prototype
 - Release-year:
 - 2020
 
