In SX Microcontrollers, SX/B Compiler and SX-Key Tool, Zoot wrote:

OK -- I'm going to wire up my servo/led controller over the next two evenings, so maybe some yes/no/maybe questions will be best :-)

- 100ohm resistors between SX pin(s) and servo signal pin(s). Yes? No? Optional?

- 22k/1mOhm resistor between OSC1 and OSC2 on 20mhz resonator? Yes? No? Maybe?

- one of Jon's code examples in NV143 has the use of a "armed/syncTimer" so that the program will move on if the correct number of serial bytes are not received. He used a 2 byte threshold (after 2 byte periods or 20 bits) of failure to RX, the program moves on. Given that in some cases my controller receives 14 bytes or so, what's a good threshold for having the program exit an RX loop? Stick with two bytes? Yes? No?

- This is kind of a Stamp question -- in my tests using the SX controller with a BS2, I've had no problem communicating both ways up to 38k4, though depending on code structure the BS2 can't always reliably read in at 38k4. In any case, Jon's code uses a delay of 15ms before TXing a byte from the SX ("to let the host get ready"). This adds 30ms to my loop time on the *host* side if I've got to SERINs in the loop. Can I get away with shortening this? It seems like the Stamp can get ready for input after issuing output commands within 5ms or so (e.g. the Ping))) firmware which inserts a 5ms delay before sending a pulsewidth reading).

- since my SX controller code allows for serial commands to change baud rate. Is there any reason not to have differing TX and RX baud rates. It would be easy enough to add in the extra variables and command? This would let me always send to the SX at 38k4 and receive at 19k2 or 38k4 depending on the capabilities of the host.

- Last but not least, Jon used 2 stop bits on his TX routine, again to give a Stamp host breathing room. ???? I don't get it. Consider me dense.

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