Transtape

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Revision as of 09:48, 6 December 2013 by Arnoldemu (Talk | contribs) (Technical)

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A Spanish Hacking Device from HM (Hard Micro, S.A.).

Transtape


Please add more info here....

Technical

  • Uses a 16KB ROM paged into memory at &0000.
  • Uses a 8KB static RAM paged into memory at &c000.
  • ROM is paged into the range &0000-&3fff when the red button is pressed and the NMI vector is executed.
  • Black button pages their ROM into the range &0000-&3fff and executes it at &0000. This checks the ROM version, and clears the extra ram if a CPC6128 BASIC ROM is found.

[code] 0000 f3 di  ;; disable maskable interrupts 0001 0100df ld bc,0df00h ;; select upper rom 0 0004 ed49 out (c),c 0006 01817f ld bc,7f81h ;; enable upper rom (mode 1 too) 0009 ed49 out (c),c 000b 31febf ld sp,0bffeh  ;; setup stack which is not initialised after reset

000e 3a02c0 ld a,(0c002h)  ;; read BASIC ROM version number 0011 fe02 cp 02h  ;; CPC6128? 0013 cc2e0c call z,0c2eh  ;; erase extra RAM

this appears to set it up for a reset..

0016 210000 ld hl,0000h 0019 e5 push hl 001a e5 push hl 001b c30038 jp 3800h  ;; I think the hardware monitors for address 3800h and if found disables the ROM [/code]

  • Uses NMI
  • When a write happens to their RAM it appears to write through to the RAM behind??
  • Menu code is at offset &3810 and is copied into RAM at &A200.
  • Uses port FBF0 (output), FBFF (input). Don't know the exact functions yet.

writing 0 to fbf0 disables it's internal rom.

Pictures

Manual

Downloads

Weblinks

Some info can be found here (French)