Hi Andrew,
I have a PIC based solution currently in the prototype stage. It uses a PIC18F4455 and drives a Yeasu AZ/EL rotor without the Yeasy control box.
The PC sends information to the PIC (RequestedAZ,RequestedEL) and the PIC sends back status information to the PC (RequestedAZ,RequestedEL,CurrentAZ,CurrentEL,Status).
Everything is done by the PIC: - Control of the rotor motors based on either move-every-n-seconds or move-when-error-angle-is-greater-than-n - Measurement of the actual AZ/EL with 10-bit resolution - Parking when no signal has been coming from the PC in x seconds -or- an explicit park command is received - Stall protection - Some horizon protection: EL cannot go below x when AZ is y to avoid pointing into my neighbors' bedroom. - Over the top rotor control (under development) - ...
I'm using a PIC18F4455 and it is very well capable of doing all that and more. I have chosen this path for several reasons: - Eventually I want to run a tracking algorithm in the PIC too - To make the control loop shorter - To avoid dependence on the PC part specifically on safety related aspects like stall control and horizon protection. - To explore the capabilities of the PIC18 - (Because it's my job to do embedded HW/SW)
BR, -- //\arc
-----Original Message----- From: amsat-bb-bounces@amsat.org [mailto:amsat-bb-bounces@amsat.org] On Behalf Of Andrew Rich Sent: dinsdag 13 oktober 2009 12:22 To: amsat-bb@amsat.org Subject: [amsat-bb] PIC rotator control
Hello
I am re-visting a rotator controller.
I am curious, should I push the processing of the "compare and make a decision" onto the PIC, or pull that function back into the PC ?
PC is LINUX
I/O is serial
PIC is 16F877
Andrew VK4TEC
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