Last update: June 5th 2018

Ti99Hdx with UBERgrom option

Download UberHdx version 2.0 now
ti dsk image as zipped disk-image (ZIP)

This download also contains an image file EAPROM_V_UG.BIN for the AT49F040 FlashRom containing the Editor/Assembler V module with an UTILITIES menu containing:

  • DM2K 2.6
  • CF2K 2.5
  • DU2K 2.1
  • CfHdxS 2.0 (nanoPEB)
  • UberHdx 2.0 (for UBERGrom)
  • Dsk2Pc 2.1 (for UBERGrom)

Updated 5/6/2018
Bugfix in Editor/Assembler V module in the debugger Breakpoint, Single Step, and Load Interupt code in the header of page 4. Previous version always jumped to the TI99 title screen instead of returning.

UberHdx is a file / program manager special for the UBERGrom module and is derived from Diskmanager 2000. The main feature of UberHdx is that it can communicate with the Ti99Hdx server over the serial port (UART) so that in an easy way files can be copied to and from any mass storage device (DSK, HDFC, SCS, IDE) inclusive the Cf7a+'s and nanoPEB's CompactFlash card.

PgmHdx catalog
An impression of UberHdx.

See also the Diskmanager 2000 (or Dm2k) manual.

And this program also supports (if a Cf7a+ or nanoPEB is used):

  • Mount another volume for DSK1 (ctrl-1), DSK2 (ctrl-2) or DSK3 (ctrl-3)
  • Select the next volume (ctrl-D) if DSK1, DSK2 or DSK3 is the source device
  • Select the previous volume (ctrl-S) if DSK1, DSK2 or DSK3 is the source device

But this program doesn't support:
  • Formatting of floppy disks
  • Printing of catalogs
  • Copy / Move / Delete directory structures


To use the UBERGrom device for the Ti99Hdx project you only need to add a TTL to RS232 converter to the UBERGrom's UART connection and create a cable to connect this RS232 serial port to a COM-port of the PC.

A TTL to RS232 converter can be found in many variations on the internet for not even a fist full of dollars.

The UBERGrom's UART must be mapped at the (last) GROM base >983C and GROM slot >A000. This is the same address selection as for the Terminal Emulator program TIMXT for the UBERGrom from Insane Multitasker.

The program UBERHDX1 can be used for transferring files to and from the PC. The COM port settings for the PC program Ti99Hdx are 38400 Baud, 8 databits, even parity and one stopbit.

The UBERGrom
The UBERGrom with TTL to RS232 converter and
the flashrom AT49F040.
The UBERGrom
To make use of the UART you need to add a TTL to RS232 converter.

Serial cable

For connecting the serial interface of the TTL to RS232 converter to a COM port of only three signals are needed. It depends on the 9 pin SUBD connector (male/female) if pin #2 is RXD (male) or TXD (female) and pin #3 is TXD (male) or RXD (female).
        #1 - Not connected
        #2 - RXD (or TXD)
        #3 - TXD (or RXD)
        #4 - Not connected
        #5 - GND
        #6 - Not connected
        #7 - Not connected
        #8 - Not connected
        #9 - Not connected

The UBERGrom's UART doesn't have any signal to detect if the Ti99Hdx program is running on the PC. If the Ti99Hdx server isn't there the program UberHdx1 just times out.