Hi, I have a small project with main target of controlling external solenoid. Functionality of the main board can be described as follows:
(i) retrieve data from simple keyboard (4+4 pins, 16 keys). Keyboard is for entering a password
(ii) control external solenoid (230 VAC, 10 W) when external authorization is approved
(iii) retrieve data from mass flow meter through RS485
(iv) communicate with PC through RS232: sending string entered on the small keyboard, listen for password authorization and signal that transaction is allowed to be started, sending data from the flow meter.
There will be also a bootlader installed at ATMEGA644PA thus the program can be easily changed without touching the board.
Input voltage available is stabilized 24 VDC which is planned to be transformed linearly via 7805 to 5 V. Power lost will be about 1 W.
Draft of the control board scheme is attached.
Could I ask you for checking this scheme a little bit and discussing about this project in general. My job is software developer and my knowledge of electronics is a little bit limited yet.
Thank you,
Martin Halama
(i) retrieve data from simple keyboard (4+4 pins, 16 keys). Keyboard is for entering a password
(ii) control external solenoid (230 VAC, 10 W) when external authorization is approved
(iii) retrieve data from mass flow meter through RS485
(iv) communicate with PC through RS232: sending string entered on the small keyboard, listen for password authorization and signal that transaction is allowed to be started, sending data from the flow meter.
There will be also a bootlader installed at ATMEGA644PA thus the program can be easily changed without touching the board.
Input voltage available is stabilized 24 VDC which is planned to be transformed linearly via 7805 to 5 V. Power lost will be about 1 W.
Draft of the control board scheme is attached.
Could I ask you for checking this scheme a little bit and discussing about this project in general. My job is software developer and my knowledge of electronics is a little bit limited yet.
Thank you,
Martin Halama
Attachments
-
298.5 KB Views: 10
-
45.6 KB Views: 19