Mitchy's Geeky Clock
- Details
- Published: Thursday, 01 April 2010
- Written by Graham Mitchell
- Hits: 10541
Credit where credit is due, this project was inspired by Jon Chandler's Clock for Geeks.
After reading through one of Jon Chandlers recent projects, I was rather inspired to make my own! The Geek Clock is a great spin on a more then well known concept - displaying time. His method employs a Servo, PIC and a little intuition.
Design
Rather then using the paper clock face like Jon did, I experimented with a few other methods to spice up the presentation. At work, we recently acquired a large Vinyl Printer and Gerber Cutting machine. Long story short, we can make all sorts of decal stickers (very handy indeed!!). It was a pain staking ordeal creating the clock face on the Omega software (for the vinyl printer/cutter) as it was written in the early 90's and very vector based graphics. In the end I got something that looked like a clock.
Originally I was going to use the decal cut-outs to create the clock face - problem was the decal stickers would not adhere well to wood. I could have used glue, though any excess would have lead to a bad varnish job. Then it struck me - what if I use the external part of the sticker as a template - to paint through? The result was perrrfect! We're about due for a montage:
Figure 1. Preparing the Decal.
Figure 2. Paint is dry, time to start peeling!
Figure 3. Slow process, don't want to mess it up!
Figure 4. Removing the little inner bits.
Figure 5. Light at the end of the tunnel. Ready for the servo cut-out and then some varnish.
Figure 6. The Final Product!
The Hardware
The Geek Clock controller was built on the infamous TAP-28 PIC Development Board. I also used the TAP-28 DS1307 RTC Daughter Board and got to it.
I used the DS1307 as it offers an automatic low power mode (to continue clocking time with the absence of main power). It's highly accurate (PIC's generally drift from a few seconds to a minute or two each month), and cheap!
The Code
Before I get started on the code - it should be noted that the clock needed calibration first. This was done by using a slightly modified version of Jon's.
Calibration Program
// Designed to calibrate the geek clock. // Allows the user to 'wind' the potentiometer to control the servo. // The servo can be controlled from 400uS to 2400uS pulse widths. // Displays UART data continously to inform user of calculated position. Device = 18F2520 Clock = 32 Config MCLRE = Off // only one servo in use #option Servo_NumberOfServos = 1 // all includes can be found @ digital-diy.com ("Swordfish - Module Pack") Include "InternalOscillator.bas" Include "utils.bas" Include "USART.bas" Include "convert.bas" Include "ADC.bas" Include "Servo.bas" Dim CalcServoPosition As Word // sample ADC, return a value from 400 to 2400 Function GetDesiredServoPosition() As Word Result = 400 + ((ADC.Read(0) * 2000) / 1023) End Function // main program start... // configure USART USART.SetBaudrate(br38400) // configure ADC ADC.RightJustify = True ADC.SetConvTime(FOSC_16) // enable servo module Servo.On While True // get desired servo position CalcServoPosition = GetDesiredServoPosition // update servo position ServoPosition(0) = CalcServoPosition // inform user of calculated servo position USART.Write("Servo Position = ", DecToStr(CalcServoPosition), 13,10) // delay for 200mS DelayMS(200) Wend
Geek Clock Controller
// Geek Clock, by Mitchy // for more info: http://digital-diy.com/projects/168-mitchys-servo-clock.html // Inspired by Jon Chandlers Servo Clock! Device = 18F2520 Clock = 32 Config MCLRE = Off // one servo in use #option Servo_NumberOfServos = 1 // all includes can be found @ digital-diy.com ("Swordfish - Module Pack") Include "InternalOscillator.bas" Include "Servo.bas" Include "ServoCal.bas" Include "USART.bas" Include "DS1307.bas" Include "Convert.bas" Const AdjustSpeed = 10 // #mS to decrease delay by on each adjust Dim USART_Second_Poll As Byte, // USART polling registers USART_Minute_Poll As Byte, // USART_Hour_Poll As Byte, // AdjustDelay As Word, // AdjustTime As PORTB.5 // Time Adjust Switch // calculate # of minutes elapsed during day // and display calibrated servo position based on that info Sub DisplayServoTime() Dim TotalMinutes As LongWord If Time.Hour < 12 Then TotalMinutes = (Time.Hour * 60) + (Time.Minute) Else TotalMinutes = ((Time.Hour-12) * 60) + (Time.Minute) EndIf ServoPosition(0) = TimeValues(TotalMinutes) End Sub // update the clock registers, then call the servo update sub Sub UpdateClock() DS1307.Read(Time, Date) DisplayServoTime End Sub // check if the Time Adjust pin is pressed // if it is, then increment minutes - also, // if the button is held, then speed the process up! Sub CheckAdjust() If AdjustTime = 0 Then Time.Second = 0 Inc(Time.Minute) If Time.Minute >= 60 Then Time.Minute = 0 Inc(Time.Hour) If Time.Hour = 24 Then Time.Hour = 0 EndIf EndIf DS1307.Write(Time,Date) DisplayServoTime DelayMS(AdjustDelay) If (AdjustDelay-AdjustSpeed)>1 Then Dec(AdjustDelay,AdjustSpeed) EndIf Else AdjustDelay = 300 EndIf End Sub // check any time parameter has changed, if it has then display on UART Sub SendUART() If USART_Second_Poll <> Time.Second Or USART_Minute_Poll <> Time.Minute Or USART_Hour_Poll <> Time.Hour Then USART.Write(DecToStr(Time.Hour, 2),":",DecToStr(Time.Minute,2),":",DecToStr(Time.Second,2),13,10) USART.Write(DecToStr(Date.Day,2),"/",DecToStr(Date.Month,2),"/",DecToStr(Date.Year,2),13,10) USART_Second_Poll = Time.Second USART_Minute_Poll = Time.Minute USART_Hour_Poll = Time.Hour EndIf End Sub Sub Initialise() // configure PORTB INTCON2.7 = 0 // enable internal pullups Input(AdjustTime) // if the DS1307 device has not been enabled, we need to give // it some default values - here we set for 0600 // on the 1st Jan 2010... If Not Enabled Then Time.Hour = 6 Time.Minute = 0 Time.Second = 0 Date.Day = 1 Date.Month = 1 Date.Year = 10 DS1307.Write(Time,Date) EndIf // initialise servos UpdateClock Servo.On // configure UART module USART.SetBaudrate(br38400) // initialise variables AdjustDelay = 300 USART_Second_Poll = 255 USART_Minute_Poll = 255 USART_Hour_Poll = 255 End Sub // main program start... Initialise While True UpdateClock // grab current time, update servo position CheckAdjust // check if user is trying to adjust time SendUART // display current time via UART Wend
ServoCal.bas
Module ServoCal // replace constant data with that of your own results with the spreadsheet found at http://digital-diy.com/forum/download/file.php?id=290 Public Const TimeValues(721) As Word = ( 1966,1964,1963,1961,1960,1958,1957,1955,1954,1952,1951,1949,1948,1946,1945, 1944,1941,1939,1937,1935,1933,1931,1929,1927,1925,1923,1921,1919,1917,1915, 1913,1911,1909,1908,1906,1904,1903,1901,1899,1898,1896,1894,1893,1891,1889, 1888,1886,1884,1882,1881,1879,1877,1875,1874,1872,1870,1868,1867,1865,1863, 1862,1860,1858,1856,1854,1853,1851,1849,1847,1845,1844,1842,1840,1838,1836, 1835,1833,1832,1830,1829,1828,1826,1825,1823,1822,1821,1819,1818,1816,1815, 1814,1812,1810,1809,1807,1806,1804,1802,1801,1799,1798,1796,1794,1793,1791, 1790,1787,1785,1783,1780,1778,1776,1773,1771,1769,1766,1764,1762,1759,1757, 1755,1753,1752,1751,1750,1749,1747,1746,1745,1744,1743,1741,1740,1739,1738, 1737,1735,1733,1731,1729,1727,1725,1723,1721,1719,1717,1715,1713,1711,1709, 1708,1706,1705,1703,1702,1701,1699,1698,1696,1695,1694,1692,1691,1689,1688, 1687,1685,1683,1682,1680,1679,1677,1675,1674,1672,1671,1669,1667,1666,1664, 1663,1661,1659,1658,1656,1655,1653,1652,1650,1649,1647,1646,1644,1643,1641, 1640,1637,1635,1633,1630,1628,1626,1623,1621,1619,1616,1614,1612,1609,1607, 1605,1603,1601,1600,1598,1597,1595,1593,1592,1590,1589,1587,1585,1584,1582, 1581,1578,1576,1574,1572,1570,1568,1566,1564,1562,1560,1558,1556,1554,1552, 1550,1548,1546,1544,1542,1541,1539,1537,1535,1533,1532,1530,1528,1526,1524, 1523,1521,1519,1518,1516,1515,1513,1511,1510,1508,1507,1505,1503,1502,1500, 1499,1496,1494,1492,1490,1488,1486,1484,1482,1480,1478,1476,1474,1472,1470, 1468,1466,1464,1462,1461,1459,1457,1455,1454,1452,1450,1448,1447,1445,1443, 1442,1439,1437,1435,1433,1431,1429,1427,1425,1423,1421,1419,1417,1415,1413, 1411,1409,1407,1406,1404,1403,1401,1400,1398,1397,1395,1394,1392,1391,1389, 1388,1386,1385,1383,1382,1380,1379,1377,1376,1374,1373,1371,1370,1368,1367, 1366,1363,1361,1359,1357,1355,1353,1351,1349,1347,1345,1343,1341,1339,1337, 1335,1333,1331,1329,1327,1326,1324,1322,1320,1318,1317,1315,1313,1311,1309, 1308,1306,1305,1304,1303,1302,1300,1299,1298,1297,1296,1294,1293,1292,1291, 1290,1287,1285,1283,1281,1279,1277,1275,1273,1271,1269,1267,1265,1263,1261, 1259,1257,1255,1253,1251,1249,1247,1245,1243,1241,1239,1237,1235,1233,1231, 1230,1228,1227,1225,1224,1222,1221,1219,1218,1216,1215,1213,1212,1210,1209, 1208,1206,1204,1203,1201,1200,1198,1197,1195,1194,1192,1191,1189,1188,1186, 1185,1183,1181,1179,1178,1176,1174,1172,1171,1169,1167,1165,1164,1162,1160, 1159,1156,1154,1152,1150,1148,1146,1144,1142,1140,1138,1136,1134,1132,1130, 1128,1126,1124,1123,1121,1120,1118,1117,1115,1114,1112,1111,1109,1108,1106, 1105,1103,1102,1101,1099,1098,1097,1095,1094,1093,1091,1090,1089,1087,1086, 1085,1083,1081,1079,1077,1076,1074,1072,1070,1068,1067,1065,1063,1061,1059, 1058,1056,1054,1052,1051,1049,1047,1045,1044,1042,1040,1038,1037,1035,1033, 1032,1029,1027,1025,1022,1020,1018,1015,1013,1011,1008,1006,1004,1001,999, 997,995,994,993,992,991,990,989,987,986,985,984,983,982,981, 980,978,976,975,973,972,970,968,967,965,964,962,960,959,957, 956,954,952,951,949,947,946,944,942,941,939,937,936,934,932, 931,928,926,924,922,920,918,916,914,912,910,908,906,904,902, 900,898,897,896,894,893,892,890,889,888,886,885,884,882,881, 880,878,876,874,872,871,869,867,865,863,862,860,858,856,854, 853,851,850,848,847,845,844,842,841,839,838,836,835,833,832, 831,829,827,826,824,823,821,820,818,817,815,814,812,811,809, 808,806,805,804,802,801,800,798,797,796,794,793,792,790,789, 788,786,784,782,780,778,776,774,772,770,768,766,764,762,760, 759,757,755,753,752,750,748,746,745,743,741,739,738,736,734, 733 )
Schematic
Not that the schematic matters much - the TAP-28 Development Board already has 95% of the hardware. The other 5% is the RTC Daughter Board! IF you wanted to make something similar, then message Jon Chandler and get in on the next TAP-28 production run, or you could submit the Gerber files and make your own!
As for the DS1307 board, well I did post the Gerber files for it, and the design is easy enough to make on a protoboard.
PIC
