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Calculator Information

DM32 Info

The new entry-Level do-it-all machine

Release June 2023 with Beta Firmware - community providing feedback of bugs and errors to help drive firmware development



Purchase Information

  • Date : July 2023
  • From : Swiss Micros
  • Price : CHF249 + CHF70 DHL Delivery = CHF319 = £296
  • Serial : 00812


DateDM32 VersionDMCP VersionFirmware FilesComments
20/07/23 2.03 3.50t25 2.03 F/W file Equation Solver Bug - sometimes shows LOG(0) or DIVIDE BY 0 - also Complex powers bug - Forum says “fixed in next F/W release”
01/08/23 2.04 3.50t29 2.04 F/W file Bugs I'd spotted in 2.03 now resolved
13/09/23 2.05 3.50t31 2.05 F/W file 4-line prog editor, 4-line EQN list & more
09/11/23 2.06 3.50t33 2.06 F/W file Various fixes & new features
06/05/24 2.07 3.50t36 2.07 F/W file Various new features including “remote calls” to routines in non-loaded calculator “states”
06/05/24 2.08 3.50t38 2.08 F/W file USB Speed Up and other new features
07/05/24 2.09 3.50t38 2.09 F/W file Right-align stack display option


DM32 v2.09: 2024-05-06


  Added RANDSEED to statefile
  Statefile parsing enhancements
  Stack Right-align option (see in doc)

DM32 v2.08: 2024-03-18


  Added CPU frequency switching when powered from USB
  Added remote calls from CALC mode
  Added Extended GTO functionality (see in doc)
  Added support for automatic load of dependent states (see in doc)


  Fixed: The '0' style doesn't match register font in SHOW box
  Fixed: F3 (SST) should act only if no other key processing is pending
  Fixed: F3 (SST) long press to NULL behavior
  Fixed: Remote XEQ calls to current context
  Fixed: First remote XEQ call should clear remote call stack
  Fixed: Current state filename should be pre-selected in "Save" dialog

DM32 v2.07: 2023-12-08


  Added remote XEQ functionality (see in manual)
  Added SHOW view of EQN message
  SHOW extended to all program lines in program mode


  F2 key (i.e. debug view toggle) deactivated for non-CALC modes and during number entry
  Fixed USB disk id to 0483:5720 so it corresponds to USB MSC by STM
  Fixed: Program SOLVE ending in "NO ROOT FOUND" prevents subsequently keyed XEQ from running (until pressing [R/S])
  Fixed: Number entered as '1E-' ([E][+/-]) should be interpreted as '1'
  Fixed: Message triangle cut-off after File->Load Clean State
  Fixed: Left/right scrolling of long EQN message (i.e. EQN in PRGM mode with flag10 set) doesn't work

DM32 v2.06: 2023-11-01

  Added "Debug View" (see in manual)
  Added Step-out and Step-over (see in manual)
  SHOW box style changed to better match overall look
  Fixed: Sometimes SHOW displays "SHOW" instead of expected text on long key press
  Fixed: Wrong CLEAR menu in PRGM and EQN mode after elaborated key combinations
  SHOW hold isn't killed by shift presses (simplifies screenshot invocation)
  SHOW hold isn't canceled by screenshot
  Fixed: Integration ends on overflow when Flag5=0 (should give an integration result) .. this also fixed a problem with restarting integration after an overflow
  Fixed: Memory corruption in EQN list (reported by Raul). Exhibit itself during EQN edit by displaying "NO EQN" on other lines and all those equations are lost.

For the full list see https://technical.swissmicros.com/dm32/firmware/history.html

For current USER MANUAL see https://technical.swissmicros.com/dm32/doc/dm32_user_manual.html

RTC Correction

  • approx. error : -23ppm (-2.0s/d)
  • Correction factor C from C = 2^20 P /(10^6 + P)
  • Approximations :
    • C = 1.04858 P
    • P = 0.953674 C
  • Calculated C = 24.2

Put a text file /rtccalib.cfg in root directory of FAT drive with contents:


RTC Error

StartStopAccumulated Error (s)Rate Error (s/d)Comments
20/07/23 22/07/23 -3.5 -2.0 First 2 days initial test. -23ppm
22/07/23 22/11/23 +17.3 +0.1 with correction 24.2 (22.9ppm) applied = slightly over-corrected?
06/05/24 New period started, using Python watchcheck.py on shack laptop to monitor error rate

DM32 Info

Hardware / Firmware issue

I received the following email from Swiss Micros in 8th March 2024 explaining a hardware change that's required to early production units to ensure correct operation with the latest firmware, which allows the processing speed to increase when powered via USB (as per the DM41X and DM42).

Dear valued customer,

We appreciate your decision to purchase the DM32 calculator. 
As one of our early adopters, your support means a lot to us.


In our initial firmware versions, we restricted the CPU speed 
to 48MHz due to power limitations from the CR2032 battery. 
However, in upcoming firmware updates, we're introducing the ability 
to switch to 160MHz when powered by USB. It's crucial to note that 
upon unplugging the USB, the CPU speed must swiftly revert to 48MHz 
to prevent battery voltage drop and subsequent CPU resets.

Regrettably, we've identified an issue affecting units purchased 
before December 2023. In specific scenarios, the CPU speed doesn't 
transition quickly enough, potentially leading to calculator resets.

This may happen upon USB disconnection if the device is engaged in 
processing tasks rather than merely awaiting user input or being powered down.

All units ordered post-November 2023 have been enhanced to ensure consistent 
performance. This modification entails replacing R4 with a 22k resistor 
instead of the previous 100k one.

To address this issue, we offer several solutions:

    If you're comfortable soldering, replacing R4 is a straightforward fix. We're happy to dispatch a replacement 
    resistor to you in an envelope, see  https://www.swissmicros.com/product/r4-22k-resistor
    Alternatively, you can send your DM32 to us, and we'll replace the resistor and return it to you promptly, 
    see https://www.swissmicros.com/product/rma
    We anticipate a new batch of PCBs to be available in approximately three months. Once ready, we can send you 
    a replacement PCB. We kindly request that you return the replaced PCB to us. 


We sincerely apologize for any inconvenience caused and appreciate your 
understanding and cooperation in resolving this matter.
Thank you for your continued support and patience.


Best regards

Michael Steinmann


I find the DM32 plenty fast enough running on batteries, so I'm not necessarily going to be plugging it it to boost its performance but I do want to stay up to date with firmware changes and don't want to risk any problems, so I've ordered the replacement SMD resistor and plan to swap it myself.

Further Information

public/calculator/info/dm32_info.txt · Last modified: 07/05/24 12:37 BST by john