Doug's Brew Page
Two Tier All Grain Brewing Setup
This phase of my two-tier brewing setup will be to automate as much as possible the whole brewing process. All valves will be automated, flow sensors will be used, pumping switchers, gas flame regulators, electronic flame ignition, etc. The plan is to use a 486 or better running Linux with a TCL/TK GUI. This GUI will show current status, allow choice of multiple mashing scheduals, and allow direct intervention of all electronically controlled pieces. The software will also allow full sensor calibration at a software level.
All electronic measuring and controlling devices will wired in a drop-line fashion connected directly to a standard external serial port. All devices will use a microcontroller of some sort along with a RS232 chip to allow serial communications with the specific device. All devices id will be controlled via dip switches. All devices function type will be controlled via a hardwired jumper. A minimum of 1024 devices will be supported requiring 10b. A minimum of 2048 data values will be allowed requiring 11b. A minimum of these 4 functions will be allowed: set, query, type, test requiring 2b to represent functionality. An integrety check of 8b will be allowed. Based on these parameters a 4B stream will need to be able to be sent and received. All messages sent and received will be 4B in length. This will be a full duplex system with all data coming from the cpu over one set of wires and all data coming from the the devices over a seperate set of wires. RJ45 connectors seem appropriate for this application using 4 wire twisted pair line. A distribution panel with female RJ45 sockets would be hooked directly to the serial line. All devices would have a female RJ45 socket. All wiring could be any length using male RJ45 ends to allow easy repair and movement options.
| 0-9 | device id | 0 - N/A
1-1023 device id |
| 10-12 | function | 000 - N/A
001 - set 010 - query 011 - device type query 100 - test device return result of test |
| 13-23 | data block | +-1024
0-2047 |
| 24-31 | integrety check | possible sum of 0-23 bits (number of on bits)
sum of 0-3 bytes setting the lowest 8 |