NOTE:
	Files ending with BTT are named this way to tell the unit to burn the bootloader 
	as well as the main program. Older firmware will not recognize the BTT extension.
	If the unit does not update then change the .BTT extension to .BIN.
	
	TFB-xxx.BIN is for the FB transmitter only
     THD-xxx.BIN is for all other ZHD capable transmitters only
     ZMT-xxx.BIN is for the small ZMT and ZMT48 transmitters and hand held ZMT style plug on
     HH-xxx.BIN  is for the full sized hand held 
     CL-xxx.BIN  is for the new wide band camera link and new IFB200s
     LNK-xxx.BIN is for the the older camera link and IFB200 (not wide band)

-------------------------------------------------------------------------
---------------------------- version history ----------------------------
-------------------------------------------------------------------------
(PLEASE INSTALL BOOTLOADER V67 or V70 to fix an SD card formatting problem)

3.18A Sep 25
	Fixed TX NAME screen only allowing 7 characters

3.17Y Sep 11
	Made battery meter higher when looking at a full battery at 4.0V

3.17X Aug 5 2023
	Added ZAXNET TX audio support (experimental)

3.17W Jun 5 2023
	Small Zaxnet changes

3.17V May 25 2023	
	Fixed transport mode problem (was not following nova's transport mode)

3.17UU Nov 15 2022
	Fixed extra occurrences of ALLOW 608 screen

3.17U Apr 26 2022
	Prevented zaxnet mode from reverting back to RX mode on boot up (from TX mode)

3.17T Feb 28 2022
	Added mute function in AUDIO menu - press UP key in home screen to mute audio

3.17R Feb 15 2022
	Removed support for old ENG receiver battery meter

3.17Q Feb 8 2022
	Fixed Global TX power on/off commands
	No longer look at unit code when decoding global power down commands

3.17P Jan 19 2022 
	Fixed TX Name from possibly having old chars after it from a longer name

3.17N Jan 13 22  
	Prevented display from being at full brightness all the time on 743 and LA3
      
3.17M Dec 17 21  
	Added support for receiving transmitter name from Nova 
	Added .metadata_never_index file to SD card 
	so MACs will allow card ejection  this requires burning the bootloader
	To burn the bootloader rename the .BIN file to .BTT. That will tell 
	the unit to burn both the main program and the bootloader

3.17K Dec 6 21
	Added "ALLOW 608-614" screen for Europeans

3.17H May 8 2021
	Allowed TC source to be set to EXTERNAL (microphone input)

3.17F Jan 25 2021
	Never allow global gain change commands

3.17E Nov 17
	Removed ZNET REGS screen

317D Nov 3
	Fixed problem with zaxnet sometimes losing connection and requiring a reboot
	fixed boot loader not formatting new transcend cards

3.29 Oct 21
	We now reset the Zaxnet receiver if no packets were received over the last 2 seconds

3.28 Sep 18 
	extra ZaxLan commands work

3.26 Sep 11
	We now detect preset #1 freq and change the CL freq to it

3.25 Sep 8
	Added inverted RS232 modes in RS232 MODE menu to compensate for wiring of inputs

3.24 Sep 4 2020
	Camera Link no longer tries to power down when it sees a "low power mode" command

3.23 Aug 25 2020
	URXs can now follow the Camera Link when channel is changed (on the CL)

3.22 Aug 17
	CL: added support for LEFT DATA input mode

3.20 Jul 27 2020
	Prevented some factory settings from forgetting their settings


3.17 Mar 19
	Fixed settings problem starting in 3.04 that could cause strange behavior
	WARNING: Versions 3.04 thru 3.10 had problems accessing SD cards
	WARNING: Versions 3.09 thru 3.16 had settings problems that could 
		cause the unit to act strange (installing 3.17 should fix it)

3.16 Mar 16 *** DO NOT USE ***
	modified Zaxnet behaviour

3.15 Mar 11 *** DO NOT USE ***
	increased power down voltage from 3.1V to 3.12V 
	we now properly stop recording when the battery runs down

3.14 Mar 5 2020 *** DO NOT USE ***
	increased file size limit off QRX file from 0x70000 to 0x78000 to accommodate QR2-424.bin

3.13 Feb 28 (BETA) *** DO NOT USE ***
	re-wrote standby-wake-up firmware to make it more reliable

3.12 Feb 27 *** DO NOT USE ***
	added new gain calibration for factory
	 
3.11C Feb 19 2020 *** DO NOT USE ***
	Experimental CL version: allowed ZHD96 selection on a CL3

3.11 Feb 10 *** DO NOT USE ***
	ZMT,FLEX: on bootup shut down if battery voltage less than 3.1V

3.10 Feb 3 *** DO NOT USE ***
	fixed some SD cards not being recognized

3.06 Sep 15 *** DO NOT USE ***
	ZMT-PH: increased switcher voltage at 45V setting by 10%

3.04 Sep 18 *** DO NOT USE ***
	allowed sending of MRX-xxx.bin firmware file for MRX414 module

3.00 Aug 27 2019
	fixed possibly unreliable Zaxnet reception that started occurring around v2.58
	removed Low Power IFB mode (set to OFF now)
	removed a some debug text in ZAXNET MODE screen (set DBITS to 2 to make it re-appear)

2.94 Jul 27 2019
	added TC SOURCE menu back to SPORT model

2.91 Jun 12 2019 (may be labeled as 2.90)
	made lowest HPF setting limited to 70Hz to prevent noise

2.90 Jun 10 2019
	forced Low Power IFB mode to ON all the time on ZMT, SPORT, FLEX and removed menu
	forced TCSOURCE_IFB for SPORT (and FLEX) models and removed menu

2.89 May 31 2019
	disabled ZHD48 mode to prevent freeze (to use ZHD48 mode install version 2.67)

2.88 May 15 2019
	Added support for new individual power down commands
	Added support for new STANDBY low power command
	Made Low Power IFB mode less aggressive to prevent 4 second pauses in TimeCode reception
	Fixed displaying of LOW2 text even though unit was not in LOW2
	Changed LOW2 text to "TXOFF"

2.86 Mar 6
	CL3: made sure right audio channel is valid even when in MONO/XR mode 
	(for IFB transmit mixer for CL)


2.84 Feb 19 2019
	added support for sending URX firmware file


2.81 Dec 7 2018
	now use ChangeChannelRaw() for all calibration routines
	we now change channel when calling InitSynth	
	merged some changes from 900MHZ version

2.78J Oct 23
	tweaks to standby mode timing

2.78H Oct 23
	made standby mode power off when battery gets low 
	dimmed OLED after a while in standby mode	

2.77 Aug 8
	added "Transmitted transport mode" char to lower right corner of IFB MODE screen

2.76 Aug 1
	CL: allowed the unit code to be set to "ALL"

2.75 Jul 23
	added special condition when TVchMax is set to 620MHz: removed range 608-613.9 and 616-620
	removed last frequency selection in channel limits so instead of limiting to 600MHZ we now limit to 599.9 MHz

2.73 Jun 27
	CL: fixed problem with transmit power on camera link that was introduced around v2.59

2.70 Jun 14
	HH: scaled keys with battery voltage so power down key works below 3.5V
	HH: better card key detection when battery is dead
	
2.67 Jun 5 2018
	ZMT48: increased processor speed so ZMT-48 has more horsepower (to prevent freezing)

2.57	Mar 10 
	(added support for hand held model)
	HH: fixed LED RING MODE menu from going too high (rolled back to fake OFF mode)

2.58 Oct 24 2017
	fixed TRX-FB causing IFB audio reception to dropout every few minutes

2.55 July 14
	many changes for supporting ZMT-48 hardware

2.18 Jun 26
	fixed Battery Cal screen not saving its setting even when pressing menu key

2.17 Jun 14
	made it so we don't write potentially bad data to ROM if it is not read properly
	revived RecallFactoryParms menu and made some changes (do not use this menu)
	
2.16 Jun 13
	changed battery meter curve on LT style products (with only one AA battery)

2.14 May 24
	nothing changed significantly here

2.13 May 24
	added audio meter to Phantom screen

2.12 May 23
	changed TX power labels to 25,50,75,75 mW

2.11 May 23  (boot V32)
	fixed boot loader not reading small ROM (could not format a card)

2.08 May 19
	added program ERX screen to ZFR (only when in IFB TX MODE)

2.07 May 18
	removed 1K notch filter from ZMT build 
	default 2Knotch to OFF in ZMT build

2.05 May 16
	removed blank screen reference from OLED brightness screen on ZMT products
	prevented gain screen from printing debug info when TONE is on
	removed INVERT DISPLAY screen
	removed battery type menus from ZMT

2.04 May 15
	fixed TX format screen in ZFR
	added product model number to INFO screen

2.03 May 15
	removed FormatCard screen and HP screen from home menu on ZFR400
	added frame rate to lock screen

2.01 May 5 2017
	added support for ZFR400 model

2.00H Apr 6
	Special version for a hardwired ZMT48 prototype units that only put out 48V

2.00 Apr 4
	fixed ROM being written every time the unit boots up

1.65 Apr 4
	bootloader changed to 29

1.64 Apr 3
	added support for REVD SPY3 boards (needed for small ROM to work)

1.63H Mar 20
	special version for a hardwired ZMT48 that only puts out 48V
	for Jan - it allows access to the ROM and disables the DAC TX line.

1.63G Mar 16
	fiddled with RX chip init and reduced some RX init delays

1.63F 
	finer power voltage tuning.  ROM access cannot work it appears.

1.63A	Mar 7 2017
	added model MODEL_SPY48
	support for 48V testing on SPY48
	hooked up 48V on off ctrl to PACTL state routines
			
1.61 Feb 28
	added Notch2k and HighPassFilter screens to ZMT

1.60 Feb 14
	reduced test tone mode TONE_FULL_SCALE so it would not clip

1.59 Feb 3
	forced ZMT to be in "QRX" style battery mode (as opposed to ENG style)

1.58 Feb 2
	fixed problems with changing channels requiring a reboot
	fixed problems with audio and/or TX power not coming back after LOW2 powerdown mode

1.57 Feb 1 (do not use)

1.55 Jan 31  
	fixed problem with blank LOCK screen causing crash when button is pressed
	reduced timeout delay so removing an SD card does not screw up the user interface
	fixed IFB reception problems in ZMT transmitter

1.51 Jan 30 (do not use)
	added TX AUDIO PHASE INVERT screen to factory menu 
	which inverts phase of transmitted and recorded audio.

1.49 Jan 28  (do not use)
	ZMT: added totally black screen in lock screen for ZMT
	ZMT: fixed problem with auto-power-down down 
	
1.47 Jan 27 (do not use)
	pulled in old ZAXNET code from v1.38 to prevent possibility of RX mode stopping for no reason

1.46 Jan 23 
	fixed single char blank screen not updating at all (could never get out of it)

1.45 Jan 20
	fixed power down sequence  (with menu key)
	fixed blank screen in Lock mode with single Transport Mode character
	Added more status to ZAXNET MODE page: 
	  Packet count, Timecode packet count, remote control packet count and ZNET unit ID in parentheses
	turn off record when powering down
	added IFBlowPowerMode (experimental)
	
1.37 Jan 9
	new bootloader V25 which does not overwrite bootloader when burning a program

1.36 Jan 6
	FB: fixed ZHD96 recordings not being played back thru earpiece
	FB: changed FB product RXer display on boot

1.33 Jan 4 2017
	BootLoader BurnROM: added retries 

1.32 Jan 4 2017   --------------- 2017 -----------
	fixed battery type page not having NIMH selection

1.31 Dec 23                                                                               
	changed "blank display mode" to only occur in LOCK screen and when OLED brightness=21.29 Dec 14
	fixed "blank display mode" not updating when transport mode changes
   	fixed battery and transport status not being transmitted to RXer when in ZHD48 mode
	removed "powering down" screen from LA build                                         
                                                                                          
1.29 Dec 14                                                                               	
	BATTERY METER SHOULD BE MORE OR LESS FIXED IN THIS VERSION FOR LA3
	fixed problem when holding menu key to get to top menu                               	
	removed "(CARD)" text from TOP SWITCH menu
	changed battery calibration algorithm 
	fixed battery cal screen from not saving into NV memory

1.21 Nov 21
	fixed OLED BRIGHTNESS screen  not displaying second line
	fixed -20dB tone line on audio meter not being accurate

1.20 Nov 19
	fixed rec-beep being twice as fast as it should be
	fixed test tone menu text
	added TimeCode output level screen in FB version
	fixed harsh clipping possibility in FB headphone audio

1.19 Nov 18
	fixed "MUTE" text from being printed is a strange place (for FB)
	added "Press CARD key 3X to get to Ext menu" feature to ZFR's TRANSPORT SCREEN
	added TC Output Mode menu to FB's Timecode Menu

1.18 Nov 18
	fixed IFB record beep timer not working 
	added TC output mode screen to Audio menu in FB transmitter

1.17 Nov 14
	moved ZFR RECORD FORMAT screen to Audio menu (for STEREO vs MONO setting)

1.14 Nov 5
	added FULL SCALE choice in TEST TONE menu
	added 2K test tone option to TEST TONE menu

1.11 Oct 21
	added mute switch support for FB product (in AUDIO menu)
	prevented an FB from burning a THD version of software and vice versa

1.10 Oct 20
	added check to lock settings for a few seconds if low battery detected 
	to prevent corrupted settings when a dead battery is cycling

1.09 Oct 3
	moved some menus around for the FB transmitters
	put all TrxFB-related menus in SETUP MENU
	added zaxnet debug screen in factory menu

1.06 Sep 8
	many improvements to standby screen 

1.04 Sep 2  (also made FB version)
	FIXED ZHD48 MODE THAT WAS BROKEN IN v1.02 and 1.03
	fixed ZHD96 mode not playing back 
	ZHD96 and XR modes are now interchangeable when recording and playing back
	These modes are not interchangeable with other modes when playing back so
	if the TRX is transmitting XR, it cannot playback something recorded in MONO mode.
	We now display "NO PLAYBACK IN THIS MODE" if playback not supported in current TX format

