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01/12/2021 6:15 PM
@Nomad As a general rule Roasting should not exceed 20 min to second crack You are describing is baking

12/31/2020 2:39 PM
I trying another 2 cups at 200 for 45 min

12/31/2020 2:38 PM
I have a questions.. im trying to experiment with riasting.. i roasted 3 cup of nicaraguan at 200 degrees for 1 hr and 30 min.. is that to long?

12/17/2020 11:16 AM
Snow again in NC.

12/13/2020 3:51 PM
I didn't realize snow was forecasted for this neck of the woods

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Issue affecting HTC/HTShield/RL-HT-CTRL users
The following advice note is being issued jointly by GreenBean and myself and describes a very rare occurrence. If you have experienced the issue described in the advice note on your roaster, or you are concerned that this issue may affect your roaster, please email the supplier of your board to obtain a plug in replacement 20-pin CPU chip with the revised firmware.

Advice on an issue affecting a small number of Hottop roasters fitted with HTRI boards**

Description of the issue:

1. On a small number of B-2K roasters fitted with HTRI boards** pressing eject can result in the Hottop shutting down (control panel reset) without ejecting the beans or cooling. This has only been observed on 2 B-2K roasters and only in the following very specific circumstances when all of the following apply:

1. Preheat has been completed.
2. The roaster is being externally controlled i.e. connected to a computer via a USB cable.
3. The external control program (RoastLogger, Artisan or other control software) has the fan set to 0%
4. Eject is pressed when all of the above apply


Investigation of the issue has highlighted that the inrush current when the rear and cooling fans are started is close to the tripping current of the Hottop 12V DC power supply. With certain roasters and, in particular, certain fans, the inrush current can be sufficient to trip the power supply which temporarily shuts down the roaster and resets the control panel.


It is recommended that the fan is always set on 30% or above at the end of a roast before pressing eject. In testing this issue is resolved if the external controlling program has the fan set on 25% or above when eject is pressed (as the fans are already spinning this limits the inrush current). Most roasters would always have the fan on towards the end of the roast to clear the increasing smoke as the roast nears completion.

Hottop models affected:

This issue has only been reported by one B-2K user and, in controlled testing, reproduced on one other roaster when fitted with either B-2K or P-2K control boards. In testing we have not been able to reproduce this behaviour on a Hottop B or P roaster. Whilst the problem has not been reported, or experienced in testing, on roasters other than the B-2K and P-2K, it may occur on some other roasters especially if the fans have a higher inrush current than the average.

As most users would always have the fan on towards the end of the roast they may not have experienced this issue even though their roaster is susceptible to it.


As of 1-April-2014, firmware used on the HTRI boards** has been updated to provide a soft start to the fans when eject is pressed. This avoids the problem by greatly reducing the inrush current to the fan at eject. If your HTRI board** was shipped to you after 1-April-2014 then it already has the updated firmware.

A plug-in replacement 20-pin CPU chip with the revised firmware is available to any user of an HTRI board** who has experienced this problem on their Hottop roaster, or is concerned that their roasting practices may make their roaster susceptible to this problem. Please contact JimG or GreenBean to arrange for a free CPU replacement chip (you may be asked to pay postage).

Please note that the only new feature included in the updated CPU chip is the soft starting of the fan upon pressing the eject button.

** HTRI boards can be HTC+TC4C, HTShield+TC4 or RL-HT-CTRL

This advice note is issued jointly by JimG (supplier of TC4C+HTC and TC4+HTShield boards) and GreenBean (supplier of RL-HT-CTRL boards).
Update 10-April-2014

Revisions to the RoastLogger program and the RoastLoggerTC4 sketch for the TC4C or Arduino/TC4 are now available. Click the following link for more information:

The updated software limits increases in fan speed to not more than 25% per second. Testing done so far has shown that this effectively addresses the possibility of a roaster reset when abrupt fan speed changes are requested by the user.

Unrelated to the fan/reset issue on Hottop roasters, the new software also permits runtime selection of temperature scale, C or F.

There is an update available for the aArtisan.ino sketch for the TC4 boards for those using Artisan to log/monitor, or control their Hottop roaster directly.

Version 3.0 of aArtisan.ino may be downloaded here:


1) A new command (DCFAN) has been added. The new DCFAN command is nearly identical to the present IO3 command, except that DCFAN enforces a slowed ramp up (no more than 25% per second) in fan output. Some Hottop roasters have experienced unexpected mid-roast resets when applying sudden fan speed increases using the IO3 command. ALL WHO ARE USING ARTISAN TO CONTROL THEIR HOTOP ROASTER SHOULD CHANGE FROM IO3 TO DCFAN TO AVOID THIS PROBLEM.

2) The serial communication rate has been increased to 115,200 baud.

3) Temperatures are now logged to 2 decimal places. This was requested by the developers of Artisan to assist in RoR calculation.

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