Digital & Binary clock with thermometer & hygrometer

Here we have a clock. It's not "another clock". It has digital and binary 

output. It also has a thermometer and a hygrometer. It's not "another 

thermo-hygrometer". It display's absolutely humidity (gr/m3) also.

Schematic

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MCU

I build it around Microchip PIC16F917, with internal Oscillator at 4MHz. 

I also build a serial port programmer, so I can programming it on-line, 

using the DL4YHF WinPic.

 Download source code in .asm

Clock

I use a RealTimeClock Maxim DS1305. The RTC backup power is a 

supercapacitor (0,22F). I test  it for 4 weeks, works fine. For this 

reason it don't have the capability to change the time, but you can 

do small-corrections. Once you push the button, the seconds change 

to 30, with no effect to minutes, hours etc. The routine is in lines 

1878-1887 "sec30".

You set the time when you program the PIC. You have to program 

two times. The first time without line 91 (goto  rdtime). The 

routinessetDS and settime is execute.

SetDS is setting RTC's control and trickle charger registers. In the 

settime routine, you set the time. After this, you add line 91 (goto  

rdtime) and you reprogram it. Now the routines do not execute. RTC 

can keep the setting and time at least for 28 days. The routinesDST3 

and DST10 are for DaySavingTime. The check register is flag, 1. The 

checking routine is in lines 434-460. In the last Sunday of March, the 

02:00 o'clock became 03:00 o'clock. In the last Sunday of October, the 

02:00 o'clock became 01:00 o'clock. I set the RTC for 12H mode, leds 

for 12H and display for 24H.

Temperature - Humidity

I use a digital humidity and temperature sensor Sensirion SHT11.
I bought it in a PCB, with the pull-up resistor and decoupled capacitor 

ready in place.
Measurements make every 10 seconds.
At 00, 20 and 40 seconds it measures the temperature and calculate 

the temperature and Absolutely Humidity ("gr/m3" grams at cubic meter of air).
At 10, 30 and 50 second it measures the humidity and calculate the 

Relative Humidity (%).
The check register is flag, 0. The checking routine is in lines 464-475.
The measure temperature routine is in lines 477-514 "measTEMP" 

and lines 625-714 "measure".
The calculate temperature routine is in lines 1793-1820 "calcTEMP".
The measure Relative humidity routine is in lines 560-590 "measRH" 

and lines 625-714 "measure".
The measure Absolute humidity routine is in lines 515-555 "measAH".
The calculate Relative humidity routine is in lines 717-1470 "calcRH".
The calculate Absolute humidity routine is in lines 1473-1728 "calcAH".

LCD display

I use a Chinese display 2line, 24row, with backlight. I drive it with a 

sift register T.I. 74164.

LED display

I use bright leds. 7 green with 8,2K resistors for seconds, 7 white with 

5,6K resistors for minutes and 5 blue with 560R resistors for hours.The 

maximum current for leds is about 17mA, so I don't have to drive them 

with transistors.

PCB

The PCB build in DipTrace software.  Download DipTrace files here
BEFORE PRINT:
1.      In print preview click on "Objects" tab. UNCKECK Assy and Silk
2.      CHECK Mirror
3.      CHECK Print in black only
4.      BE SURE print scale 100%.