TheBackShed.com

Forum Index : Microcontroller and PC projects : Micromite Explore-40

Author

Message

circuit
Senior Member

Joined: 10/01/2016
Location: United Kingdom
Posts: 276

Posted: 06:13pm 10 Jul 2025

Copy link to clipboard

Print this post

Upon seeing the cover of the August edition of Practical Electronics magazine, I was rather excited to see a new embodiment of MMBasic design in what is named the "Explore-40". This took me back to the days of the Explore 64 and so forth. Wow! What is this Explore-40? Straight into the article, I can only say that I am indeed rather puzzled and bewildered by this design. It is basically an MX170 with a microbridge stuck on a picomite-sized board. What the...? The kit costs £21! What on earth is the point of this? What am I missing? Apparently it allows MMBasic to be used on the Pico backpack from 2023 - and that allows the use of a microSD card, stereo audio and a 3.5" LCD panel! Eh, it seems that I have been working miracles with my £1.50 PicoMite loaded up with the 6.00.02 firmware. (yes, I have just downloaded 6.00.03; thanks, Geoff).

Am I missing something here? Anybody with any thoughts?

Volhout
Guru

Joined: 05/03/2018
Location: Netherlands
Posts: 5058

Posted: 07:25pm 10 Jul 2025

Copy link to clipboard

Print this post

Battery operation…..

Volhout

PicomiteVGA PETSCII ROBOTS

JohnS
Guru

Joined: 18/11/2011
Location: United Kingdom
Posts: 4038

Posted: 08:12pm 10 Jul 2025

Copy link to clipboard

Print this post

Maybe an article published quite a while ago in Silicon Chip?

John

al18
Senior Member

Joined: 06/07/2019
Location: United States
Posts: 228

Posted: 10:35pm 10 Jul 2025

Copy link to clipboard

Print this post

I went to the Practical Electronics magazine website, and the last issue published was December, 2024.
No 2025 issues?

Chopperp

Guru

Joined: 03/01/2018
Location: Australia
Posts: 1095

Posted: 11:06pm 10 Jul 2025

Copy link to clipboard

Print this post

John was correct. The Explore-40 was published by SC in October 2024
Brian

ChopperP

phil99

Guru

Joined: 11/02/2018
Location: Australia
Posts: 2610

Posted: 11:11pm 10 Jul 2025

Copy link to clipboard

Print this post

Quote Maybe an article published quite a while ago in Silicon Chip?

Silicon Chip, October 2024 and is a repackaged Explore 28 from September 2019.

The main use of the Explore 28 is embedded controllers that just "do their thing" for decades as the MX170 is pretty much bullet proof and as Volhout said perfect for battery operation.

circuit
Senior Member

Joined: 10/01/2016
Location: United Kingdom
Posts: 276

Posted: 01:06pm 11 Jul 2025

Copy link to clipboard

Print this post

al18 said I went to the Practical Electronics magazine website, and the last issue published was December, 2024.
No 2025 issues?

I am a subscriber and I can assure you that I have the full set for this year; eight issues so far.

robert.rozee
Guru

Joined: 31/12/2012
Location: New Zealand
Posts: 2437

Posted: 04:56pm 11 Jul 2025

Copy link to clipboard

Print this post

unfortunately there are two errors in the Explore-40 circuit as given by SC and PE:

1. there should be a 10k pullup to 3v3 on pin 11 of the MX170. omitting this resistor is a major defect that risks making entering programming mode and uploading new firmware flakey. the problem is that while the MX170 is held in reset, pin 11 goes into a high-impedance state, allowing noise to get into pin 5 of the 1455. this creates a serial framing error 'storm' for the 1455, disrupting its operation.

2. pin 1 (GP0) of CON3 should be connected directly to pin 5 of the 1455, rather than to pin 11 of the MX170, in order to allow maximum flexibility in driving GP0 from an external source. this is a minor defect that only impacts the case where the user wishes to drive serial data into GP0 in order for the 1455 to be used as a USB-to-serial bridge independent of the MX170.

see attached E-28 schematic:
E-28 (1D) diagram.pdf

cheers,
rob :-)

Print this page

To reply to this topic, you need to log in.