BAScontrol Series Open BACnet Controllers Built on Sedona

Understanding BAScontrol Firmware

There are three production versions of firmware in the BAScontrol series. The original BAScontrol release was 3.1.x which provided support for the BAScontrol20 20-point controller and the BAScontrol22 22-point controller each functioning as BACnet/IP servers. The 20-point model supported either four relay or four triac outputs and one 10/100 Mbps Ethernet port. The 22-point model has two switched Ethernet ports and six relay outputs.

With firmware 3.2.x, BACnet/IP client capability was introduced allowing the BAScontrol22C to command or request data from another BACnet/IP server or from a BACnet MS/TP server via a BACnet/IP to BACnet MS/TP router such as Contemporary Controls' BASrouter. This allowed for remote I/O control of external BACnet points.

Firmware 4.0 was mostly done to provide MS/TP functionality in the BAScontrol22S. The BAScontrol22D is functionally equivalent to the BAScontrol22C although it uses a different Ethernet switch controller which has better availability. Below you will see a selection guide for controllers showing installed firmware. The two new models are shown at the bottom of the table.

BASControl Series of BACnet/IP Sedona Unitary Controllers

Regardless of the firmware revision, the intent was for all the controllers to retain several common features. All have eight universal inputs configurable for voltage, current (with an external resistor), temperature with built-in 10k type 2 and type 3 and 20k thermistor curves, pulse input, resistance (1 kΩ - 100 kΩ), and contact closure (voltage-free). There are four binary inputs for voltage-free contact closures, and four analog outputs (0-10 VDC). The 20-pt. models provide a choice of four relay or triac outputs while the 22-pt. models have six relay outputs. Relay outputs are rated at 30 V at 2A and intended to switch NEC Class 2 circuits. All models have the same panel mounting footprint.

All models have at least one BACnet/IP 10/100 Mbps Ethernet port. Some models have two ports using a built-in Ethernet switch. The Ethernet port(s) serves both as a BACnet/IP connection to other devices, and as an IP connection for Contemporary Controls BAScontrol Toolset which is used for live programming of the Sedona-based controller. As a web-based controller, configuration of BACnet points and the viewing of channel data is accomplished with a common web browser over Ethernet.

What features were added to firmware 4.0?

Firmware 4.0 was necessary to introduce MS/TP communication to the BAScontrol series but, it was an opportunity to optimize the controller code base to gain more application memory space. The BAScontrol series utilize a single-chip CPU with both RAM and flash along with an external serial flash memory chip. Sedona code is highly efficient not requiring much application memory space but with more complex HVAC applications a bit more memory helps. With the 4.0 upgrade, additional application memory space was created through software optimization. However, during the development process it was determined that more application memory space could be created by simply removing flag bits in the kits.scode file that are not needed with production code. This benefit would also apply to current 3.x firmware. By simply saving and restoring existing 3.x applications using BASbackup (from updated Toolset), this same reduction in memory use will be realized. Overall, optimizing firmware resulted in a memory saving that proved significant to the controller series. These and other benefits occurred with the firmware 4.0 upgrade project:

• Creation of the two new models along with support for MS/TP
• BACnet client/server on both the MS/TP and IP networks
• Additional high-temperature thermistor curve added to universal inputs
• BACnet Utility tab added to the home webpage
• Code optimization increased available application memory space
• BACnet code was upgraded to protocol revision 15 compliance level
• The multi-state object is now supported with the network variable components (NetV)
• BASbackup was tested to ensure interoperability with applications saved on older platforms

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