Sandbox ROM vs Childish Prank


On the HP41 Facebook group, a member posted the ol' SF 11 turn off trick. I recalled another prank along the same lines:

01 SF 11
02 OFF

I keyed this into my HP41CL and it failed, much to my surprise. It turns out the Sandbox ROM startup banner interferes with the AVIEW somehow. I tried it on i41CX and had the same result with the Sandbox ROM installed. Taking it out made it run like I expected.

I don't think Ángel should worry. Given what I'm trying to do here, it's hard to call this a bug. :)


Howard, you must be the only SandBox user left in the world !
Sorry it ruined your prank demo :-)

Yes its greetings banner does not yield to the other modules plugged after it, as back then (2002 if memory serves) I knew little about other ways to implement that. The name "SandBox" says it all..

I can of course change this now but it's hardly worth the effort. All other modules after it (SandMATH, 41Z, TOOLBOX, etc, etc) use "approved" calls that hand the execution back on to the OS after the code in the polling points is done - creating buffers, assigning keys, etc.

Best example is the SECURE functions in the CL_Utils module, which allows for user prompts *during* that phase, and yet it returns happily to the OS - assuming the right password is entered.



Howard, you must be the only SandBox user left in the world !

Ángel, Howard is not alone! ;)
I have it burnt into Clonix, and a couple of instances of V41, if memory serves... fond memories, maybe. Thanks for it, of course.


ok, so ¨by popular demand¨ (hey two users and counting!!! :)) I´ll redo the splash code on the SandBox... give me a few days while I dig out the archaeological construct.. should be fun to confront myself with the early sins of my MCODE days - definitely more benign than today´s!

Edited: 29 Jan 2012, 6:16 a.m.


ok, so ¨by popular demand¨ (hey two users and counting!!! :))

Ahahah... :D
Thank you if you want to venture in this! Actually mine was not a change request but an endorsement! ;)


Edited: 29 Jan 2012, 8:05 a.m.


Well well, it looks like the the needed changes weren´t that difficult - see below for the required patch, involving just patching 5 bytes at address pFE0 to pFE4:

BFE0	320	DSPTOG	display ON
BFE4 320 DSPTOG display OFF

Since it uses HalfNut lower case characters it won´t be very descriptive on the CL, specially if you have it in TURBO50 startup.


Possibly Related Threads…
Thread Author Replies Views Last Post
  HP85 Programmable ROM cardtridge 82929A-service ROM not working- inaki 2 1,871 04-25-2013, 08:08 AM
Last Post: inaki
  shelf life time of a ROM, EEPROM, EPROM vs Mask Rom Guido (Canada) 6 2,965 01-11-2013, 04:09 PM
Last Post: Thomas Falk
  Big ROM - 41 System DEMO ROM Ángel Martin 5 2,555 10-16-2012, 05:28 AM
Last Post: Ángel Martin
  HP-41 FOCAL to .ROM for Clonix/NoV's (or any other ROM-box) Diego Diaz 6 2,535 06-08-2010, 01:44 PM
Last Post: Meindert Kuipers
  NoV64 and Sandbox (and posible other >=8k roms) ZOleg 5 1,794 12-19-2008, 04:06 PM
Last Post: Diego Diaz
  PPC ROM 2C / Melbourne ROM manual ZOleg 2 1,301 12-08-2008, 08:21 PM
Last Post: ZOleg
  Annotated MCODE listing for Sandbox - Angel Martin, are you around? PeterP 3 1,308 04-26-2008, 02:53 AM
Last Post: PeterP
  ZENROM, PPC, CCD & SANDBOX Jon 2 1,049 05-03-2005, 02:33 AM
Last Post: Ángel Martin
  SandBox Sequel ROM Ángel Martin 6 1,811 02-20-2004, 02:18 PM
Last Post: Angel Martin
  Sandbox ROM question for Angel David 2 1,033 12-13-2003, 10:18 AM
Last Post: Meindert Kuipers

Forum Jump: