Design Requirements: Difference between revisions

Revision as of 07:36, 31 October 2011

Based on Arduino Mega 2560 Microcontroller
Control at least 4 doors
- 4 Form C relays for doors (5A rating)
- 2-4 Form C relays for alarm, other functions (5A rating)
Real-time clock accurate to +/- 20ppm
- Battery backup for date/time
Allow for 4 Wiegand Readers
- 6-pin format to allow control of LED/Beeper
  - PWR,GND,1,0,LED,BEEP
- Allow for wide range of pulse widths
  - 20-400uS pulses from logic high to GND
8+ Supervised alarm zones
- 4-state supervision
  - Detect faults such as zone cut/broken, short
  - Detect closed and open states
- 2-terminal design
- Include current limiting and ESD protection
On-board RS-485 support

==== Expansion Capability ====-

12-14VDC operation
- Adaptable to 24V with component changes
On-board switching PSU for 5V or 3.3V needs
Input power protection
- Reverse polarity protection
- Surge and ESD protection
- Fused input rail
External power rails
- Polyfuses or fuses for additional power outputs
- Can be on-board or on separate power distribution board

@@ Line 18: / Line 18: @@
 ** 2-terminal design
 ** Include current limiting and ESD protection
+* On-board RS-485 support
+==== Expansion Capability ====-
+* Provision for Ethernet (4xSPI pins)
+* Provision for SD card support
+* Provision for external host-mode USB support
+* Break-out of all pins, including ICSP
+==== Power ====
+* 12-14VDC operation
+** Adaptable to 24V with component changes
 * On-board switching PSU for 5V or 3.3V needs
 * Input power protection