LED toy details

Parts list

Description	Part number	qty	Unit cost
ATMega368P -16PU (32K 28pin)		1	3.95
74HC595 shift register		4	0.55
10mm red LED		16	0.16
10mm green LED		16	0.16
0.1" Pitch Single Row header strip (16 per module)		4	0.30
0.1" Pitch Single interconnect (8 per module)		4	0.30
2.2uf supply decoupling (1 per module)		4	0.07
100uF Main decoupling		1	0.18
FTDI USB-Serial converter 5V TTL level		1	11.00
16Mhz X-tal		1
100nf decoupling		2
10K ohm 250mw (cold-starter)		1

 

9600 8 n 1

All command are intended for use over a terminal with a person typing, and are human readable in ASCII. Hence a 10ms character delay is needed if pasting commands into Hyperterminal (Teraterm) or driving via application. A Windows Powershell sample test application to be attached. Commands are terminated by a carriage-return pair (CR-LF.) I.e. enter + ctrl-enter. All input is echoed back to the sender making verification of link easier. Additional information for debugging is attached to each activity, so command responses are not currently machine process-able. Commands generally follow a letter + value pair, all integer parameter values are in the range 0..255.

Example:

B:nnn

Set brightness 0=off, to 255 max (maximum brightness is actually around 90, and depends on the PWM configuration of the controller.)

prefix	Value1	Value2	Meaning
B	0..255	-	Set brightness from 0..90
L	0..4	0..255	Send value2 to shift register value1. Sets the bitmask in register
S	0..31	0,1,2,3	Set lamp to state . Sets an individual LED behavior. 0=led off 1=led on 2=blinking (on/off) 3=blinking (off-on)
R	0..255	-	Set blink rate , default=50 (50 is around 500ms)
Q	-	-	Query device state, prints out some debug counters and clears the internal debug counters: 1 – number of protocol errors??? 2 - number of buffer overflows??? 3 – buffer high-watermark

It is only possible to set LED behaviors with the S command, blinking mode 3 blinks an LED in opposing phase to mode2.
https://engxd.domain.com/lemons/DesktopExt/auth/login.aspx

Powershell Code

...

function Send-SerialMessage

{

[cmdletbinding()]

param($port, $msg)

       $msgCR = "$msg`r`n"

       $msgCR[0..$msgCR.length]| %{

              $port.Write($_)

       }

       write-verbose $msgCR

}

function Read-SerialTrace

{

       $string = $port.ReadExisting()

       while ($string -ne "") { $string| %{write-verbose "$portName: $_"};start-sleep -m 50 ;$string = $port.ReadExisting() }

}

 ...

# [System.IO.Ports.SerialPort]::getportnames()

      

       #$portName = "COM4"

       $port= new-Object System.IO.Ports.SerialPort $portName,9600,None,8,one

       write-verbose "Open port $portName"

       Write-Progress -activity "Job : $label" -status "Open Display serial port $portName" -percentcomplete 50

       $port.Open()

       $port.Handshake = "None"

       $port.ReadTimeout = 500

       # turn all leds off, from the back forwards

       Send-SerialMessage $port "B:3"    # lower brightness

       Send-SerialMessage $port "R:50"   # rate 50

       0..4 | % {

              Send-SerialMessage $port "L:$_,0"

       }

       Read-SerialTrace

...
And that's about it :-)