Author: eur.van.andel
Date: Fri Oct 3 01:35:01 2008
New Revision: 342
Added:
trunk/unvalidated/include/external/temperature/temp_tc77.jal
Removed:
trunk/unvalidated/include/external/temperature/tc77.jal
Log:
beautified and renamed temp_tc77.jal
Added: trunk/unvalidated/include/external/temperature/temp_tc77.jal
==============================================================================
--- (empty file)
+++ trunk/unvalidated/include/external/temperature/temp_tc77.jal Fri Oct
3
01:35:01 2008
@@ -0,0 +1,148 @@
+-- Title: temp_TC77
+-- Author: Eur van Andel, [EMAIL PROTECTED] Copyright (c) 2008
+-- Compiler: =2.4h
+--
+-- This file is part of jallib (http://jallib.googlecode.com)
+-- Released under the BSD license
(http://www.opensource.org/licenses/bsd-license.php)
+--
+-- Description: this library reads the TC77 temperature sensor from
Microchip.
+-- The TC77 has a 12-bit plus sign temperature resolution of 0.0625�C
+-- per Least Significant Bit (LSb). It works via the SPI protocol
+-- Specs:
+-- 1C (max.) accuracy from +25�C to +65C,
+-- 2C (max.) accuracy from -40�C to +85C
+-- 3C (max.) accuracy from -55�C to +125C
+-- 2.7V to 5.5V Operating Range, Low Power: 250uA (typ.) Continuous
Conversion
+-- Mode, 0.1uA (typ.) Shutdown Mode
+-- ----------
+-- I have several years of experience with hundreds of these sensors.
+-- They work very well: fast, good accuracy, good repeatability.
+-- If they have an offset, it can easily be calibrated in software.
+-- The hard part of using this sensor is gettting it watertigtht.
+-- It is SMD, so it needs a PCB, and a cable. Dipping in resin or
shrinking in
+-- glue-covered shrinktube works.
+-- The SPI protocol is bit-banged here and can be used with any pins.
+-- Clock data in on rising edge of clock, program must pull CS low. This
allows
+-- for multiple TC77s on the same 2-wire databus. Put a 100nF decoupling
+-- capacitor close the the TC77. If you don't, you WILL get weird data.
+-- This library assumes two pins: global bit SCK, wired to SCK of device
and
+-- global bit SIO,wired to SIO of device. SCK should be output, SIO input.
+-- Writing the status_word is not supported here.
+--
+
+-- get raw temperature of TC77
+-- output in word, right justified
+procedure read_raw_tc77(word out raw) is
+ raw = 0
+ var bit a at raw : 0 = low
+
+ for 13 loop
+ raw = raw << 1
+ SCK = low -- clock low
+ delay_1us
+ a = SIO
+ SCK = high -- clock high
+ delay_1us
+ end loop
+
+end procedure
+
+
+-- read celsius temperature of TC77
+-- output in one sbyte with zero digits, so T = +/- xxx C
+-- last bit is 1C, range is -40C ... +125C
+procedure read_celsius_sbyte_tc77(sbyte out temperature) is
+ var word raw = 0
+ var bit a at raw : 0 = low
+ var bit raw_sign at raw: 12
+ var bit temp_sign at temperature: 7 -- zero if positive, one if
negative
+ var word tmp
+
+ for 13 loop -- 13 shifts, 12 bits
+ raw = raw << 1
+ SCK = low -- clock low
+ delay_1us
+ a = SIO
+ SCK = high -- clock high
+ delay_1us
+ end loop
+
+ if raw_sign then -- below zero C
+ asm bcf raw_sign -- clear bit 13
+ tmp = 0b1_0000_0000_0000 -- 4096
+ tmp = tmp - raw -- 16th degrees below zero
+ temperature = sbyte(tmp >> 4) -- now celsius, divided by 16
+ temp_sign = true
+ else
+ temperature = sbyte(raw >> 4) -- TC77 is limited to +125C
+ temp_sign = false
+ end if
+end procedure
+
+
+-- read celsius temperature of TC77
+-- output in one sword with 2 digits, so T = xxx.xx C
+-- last bit is 0.01C , range is -40C ... +125C
+procedure read_celsius_sword_tc77(sword out temperature) is
+ var word raw = 0
+ var bit a at raw : 0 = low
+ var bit raw_sign at raw: 12
+ var bit temp_sign at temperature: 15 -- zero if positive, one if
negative
+ var bit sign
+ var dword tmp
+
+ for 13 loop -- 13 shifts, 12 bits
+ raw = raw << 1
+ SCK = low -- clock low
+ delay_1us
+ a = SIO
+ SCK = high -- clock high
+ delay_1us
+ end loop
+
+ if raw_sign then -- below zero C
+ asm bcf raw_sign -- clear bit 13
+ tmp = 0b1_0000_0000_0000 -- 4096
+ tmp = tmp - raw -- 16th degrees C below zero
+ tmp = tmp * 625 -- celsius * 10.000
+ temperature = sword(tmp / 100) -- celsius*100
+ temp_sign = true
+ else
+ tmp = raw -- 16th degrees C
+ tmp = tmp * 625 -- celsius * 10.000
+ temperature = sword(tmp / 100) -- celsius*100
+ temp_sign = false
+ end if
+end procedure
+
+
+-- read celsius temperature of TC77
+-- output in one sdword with 4 digits, so T = xxx.xxxx C
+-- last bit is 0.0001C , range is -40C ... +125C
+procedure read_celsius_sdword_tc77(sdword out temperature) is
+ var word raw = 0
+ var bit a at raw : 0 = low
+ var bit raw_sign at raw: 12
+ var bit temp_sign at temperature: 31 -- zero if positive, one if
negative
+
+ for 13 loop -- 13 shifts, 12 bits
+ raw = raw << 1
+ SCK = low -- clock low
+ delay_1us
+ a = SIO
+ SCK = high -- clock high
+ delay_1us
+ end loop
+
+ if raw_sign then -- below zero C
+ asm bcf raw_sign -- clear bit 13
+ temperature = 0b1_0000_0000_0000 -- 4096
+ temperature = temperature - raw -- 16th degrees below zero
+ temperature = temperature * 625 -- celsius * 10.000
+ temp_sign = true
+ else
+ temperature = sdword(raw) -- 16th degrees C
+ temperature = temperature * 625 -- celsius * 10.000
+ temp_sign = false
+ end if
+end procedure
--~--~---------~--~----~------------~-------~--~----~
You received this message because you are subscribed to the Google Groups
"jallib" group.
To post to this group, send email to [email protected]
To unsubscribe from this group, send email to [EMAIL PROTECTED]
For more options, visit this group at
http://groups.google.com/group/jallib?hl=en
-~----------~----~----~----~------~----~------~--~---
