Tinkering with Electronics

I recently pulled a bad Easytouch display and the contrast on the replacement made it difficult to read.  I figured I'd do a writeup on how to adjust it... Just below the 16 pin header for the LCD you'll see resistor R37, which controls the contrast.  Normally these displays use a voltage divider for contrast - and there's evidence that Pentair designed it that way but they didn't populate R38.  All you need to do is adjust R37...  but you have to figure out what value works best. I found a 5k "trim pot" (aka variable resistor), set it to 5k, and soldered it in place of R37 (don't use it at 0k because that could damage the display) I temporarily mount the new display by setting it over the header pins as if I was going to solder it... but instead of soldering I tilt the bottom of the LCD up, which puts pressure on the pins and makes decent enough contact with the LCD for the board to boot Power up the board while keeping up the LCD pressure (could use a th...

I wrote an earlier post about powering up the Intellitouch and Easytouch boards on my test bench, so I thought I'd add one about how I power up the Intellicenter... To power these boards I use a bench/lab DC power supply because it lets me see and control the voltage and current supplied to the device.  The only significant difference with the Intellicenter is the voltage used... I use 12 volts DC (vdc) on the Easytouch/Intellitouch and 24vdc on the Intellicenter. It's safe to connect a 24vdc source to the 18vac pins because the AC voltage at the input gets converted to 24vdc by the rectifiers/caps, and you can feed DC through a rectifier... I connect my leads using the polarity shown in the pic below, and if I use less than 21vdc, the the machine doesn't boot.  If you only have an 18vac source you don't need to worry about polarity. The other two 24vac input pins can be left disconnected if you don't need the valves to work, or you can use any 24vac source you'...

 A few years back I posted about the difference between an Easytouch 1 and 2... basically the Easytouch "revision 2" is a newer hardware revision but uses the same exact board and components as the Easytouch 1, except for the microcontroller which has 128k of flash instead of 64k.  This means you can update a revision 2 board with the latest 2.x firmware versions.  You can see the original article here . Since posting that article, I've wanted to swap the microcontroller on a "V1" Easytouch with one that will make it a "V2" Easytouch... I finally did it and it works!  Figured I'd document the process in case anybody else felt like tinkering... To do the swap, my first step was to get a microcontroller with 128k flash... I had an Easytouch V2 remote with a bad keypad, so I cut it open to grab a donor chip. The indoor, outdoor and wireless controllers all use the same microcontroller but they have different firmware. The reason I used a donor chip wa...

I bought a used Easytouch PSL4 system online that came with a universal outdoor controller (uoc) and a universal indoor controller (uic)... and since I needed an Easytouch 8 uic for my test bench, I figured I'd try and hack the PSL4 unit into an ET8. I knew the outdoor boards use the same basic hardware across all versions but I'd never bothered to look at the indoor controllers.  I took apart the PSL4 and laid its main board side-by-side with one from an ET8 indoor controller... predictably, they both had the exact same hardware.  So how does it know it's a PSL4 or an ET8? Here's the Software Revision of the unmodified PSL4 uic Sometimes it's just a simple matter of swapping firmware, but hardware designers often employ a hardware-based means of identifying the version, which then dictates what features the software allows.  In the case of the indoor controllers, the main boards are exactly the same - no different resistors or jumpers - but I did notice s...

Communication issues are among the most common problems people run into with their Pentair pool equipment.  The following problems can be caused by faulty communication: pressing a button on a remote or indoor controller does nothing  an Intelliflo pump won't run the schedule screenlogic can't control the system communication timeout errors show on the intellitouch indoor panel an Easytouch wireless remote or indoor panel shows "No Comm" The good news is finding the cause of these problems isn't rocket science and involves no black magic. The first thing you need to know is that Pentair systems use an RS-485 interface for serial communication between connected devices, operating at 9600 baud (8/N/1).  If you're familiar with the RS-485 standard you can skip the next section, otherwise I'd recommend giving it a quick read to get the gist... RS-485 Basics Unlike serial interfaces that have separate Transmit (TX) and Receive (RX) wires, RS-485...

I am frequently asked if the firmware on a particular Easytouch system can be updated so that a particular fix or feature can be taken advantage of.  The answer to that question is "it depends on whether you've got an Easytouch 1 or an Easytouch 2" .  Say what?! Pentair don't advertise the Easytouch systems as a 1 or a 2 but they are currently on their second hardware revision.  The first revision is referred to as the Easytouch 1, and the second is - you guessed it - the Easytouch 2... but what is the difference and why would you care? First, a smidge of background... the Easytouch (and Intellitouch and Suntouch) equipment uses the Motorola 68HC12 family of microcontrollers, now made by Freescale.  Pentair uses the MC9S12A derivative which is basically an HC12 with some performance enhancements.  The first Easytouch version, the Easytouch 1, used the MC9S12A64 which has 64 kilobytes of flash memory for storing the program or "firmware" that the boa...