HP9810A and HP9862A - ROM required?



#2

Hi everybody,

I have a calculator HP9810A and a plotter HP9862A, both connected by the corrsponding interface cable. The calculator I had repaired some time ago. Now I'm trying to get the plotter to work.

As far as I know the plotter can be controled by the calculator by the key sequences <FMT> <arrow up> and <FMT> <arrow down> which will move the pen to the position given by the x and y registers with pen down or pen up respectivily.

Unfortunately it does't work. If I'm doing one of the key sequences the display gets dark and I have to switch the calcuator off and on before I can do a next try. If the plotter interface is removed from the calculator, the key sequences don't do anything and the calculator is not blocked by them.

With an oscilloscope I have seen, that the plotter gets a signal (the control line gets activated very shortly) and gives a response to it (the flag line gets active for 4ms).

Before diving deeper into the circuits, I have a question: Is a ROM required to use the plotter? There is a ROM in the calculator labeled "PLOTTER PRINTER ALPHA 11261A". As far as I have seen the plotter gets its signals from the calculator without this ROM too. Is this ROM reuired or are the necessary routines in the ROM of the calculator already?

I have the service manual to the plotter with the schematics of it. In it no word on this ROM can be found. Unfortunately I don't have any documentation on the ROM itself. As far as I have seen, it supplies the alpha numerical printing functions for the printer build into the calculator and this work. But I don't know what and how it can do for the plotter.

Can somebody give some hints on the functionality of this ROM?

Best regards and thanks,

Thomas Falk

Edited: 7 Dec 2013, 9:50 p.m.


Possibly Related Threads...
Thread Author Replies Views Last Post
  OT: My brain is failing me again. Help with numerical / mechanical problem required. Harald 4 226 07-01-2013, 10:31 AM
Last Post: Harald
  HP85 Programmable ROM cardtridge 82929A-service ROM not working- inaki 2 204 04-25-2013, 08:08 AM
Last Post: inaki
  HP-65 logic board repair - help required Alberto Fenini 1 135 02-17-2013, 06:39 PM
Last Post: John Robinson
  Help with geometry problem required Harald 39 1,229 01-22-2013, 10:21 AM
Last Post: Walter B
  shelf life time of a ROM, EEPROM, EPROM vs Mask Rom Guido (Canada) 6 342 01-11-2013, 04:09 PM
Last Post: Thomas Falk
  [WP 34S] New GCC - Testing required Marcus von Cube, Germany 3 203 01-07-2013, 01:59 PM
Last Post: Marcus von Cube, Germany
  Big ROM - 41 System DEMO ROM Ángel Martin 5 343 10-16-2012, 05:28 AM
Last Post: Ángel Martin
  Happy Birthday HP9810A Achim (Germany) 6 249 11-03-2011, 03:12 PM
Last Post: Achim (Germany)
  WP 34S: Some testing required Marcus von Cube, Germany 27 973 10-15-2011, 11:15 AM
Last Post: Marcus von Cube, Germany
  the HP-65 required more from the user Don Shepherd 10 393 08-05-2011, 01:28 PM
Last Post: Don Shepherd

Forum Jump: