4P-ROM - Enhanced ROM for Model 4P systems

The 4P-ROM adds new features and improved performance of Model 4P systems. The new features include:

The Model III-mode ROM-image loads from floppy in less than six seconds.
Floppy booting (including ROM-image loading) is much more reliable.
Built-in diagnostics include a full 64K RAM test, disk test and video alignment patterns.
New French and German error messages.
Hard disk boot-interlock is provided. The system will not try to boot from a hard disk unless the hard disk contains a valid boot track. No more holding down the [F2] key.
Hard disk booting is available for several types of disk controllers and drivers. (See the HBUILD6 product for more information.)
Hard disk booting will wait for slower hard disk drives to come on-line. This is useful if you expect your system to reboot unattended.
A fully programmable 6845 CRT controller can be used in place of the Tandy 68045 controller.
Handles gate-array and non-gate-array systems properly. The original Radio Shack ROM does not handle the floppy disk controller on gate-array systems correctly.

Detailed instructions assist you during the installation of the 4P-ROM, which can be done in about 25 minutes. The ROM is a socketed part in all Model 4P systems, so no soldering is needed.

The 4P-ROM can also be customized with your name, address, drivers' license number, or other identifying information that is displayed on demand or when a boot fails, such as when there is no diskette in drive 0.

This customization is available when the 4P-ROM is ordered by itself or as part of HBUILD6. There is an additional $10 charge for customizing the ROM. Specify 4PBRCU0 in addition to the 4P-ROM or HBUILD6 part number. Allow an additional two weeks for order processing for any customizations. Click here for the details on 4P-ROM customization.

4P-ROM System Requirements:
CPU	Model 4P non-gate-array or 4P gate-array system.
Processor	Z80A or a superset processor, including the XLR8er accelerator. * **
Floppy Drive	Two Radio-Shack-compatible floppy drives, although one or both can be double-sided, and can be 5.25" or 3.5" media, provided the current boot ROM will boot correctly as the system stands.
Hard Drive	Any Radio Shack-compatible configuration including no drives.
Operating Systems	The following systems have been tested: LDOS 5, TRSDOS 6, LS-DOS 6, CP/M+, NEWDOS, TRSDOS 1.3/1.4.
Hardware	The 4P-ROM may be used with a SmartWatch(TM) clock chip.**
Keyboard	The Model 4P was only available in a US keyboard layout, and that is the only supported arrangement.

*: The XLR8er(TM) accelerator is supported provided that it worked with the system prior to the installation of the 4P-ROM and your system has not been modified to defeat the wait-state generation for ROM accesses.
**: There are combinations of 4P-ROM, SmartWatch, XLR8er, graphics, network and modem cards that conflict physically due to tight space in the Model 4P. If you have any of these items, make a survey of space around the boot ROM socket and make sure no other object hangs over the ROM socket (except the SmartWatch) and no other object comes within 3/8" on any side of the boot ROM socket.

Ordering Information

Important: The HBUILD6 package contains the software that allows systems to boot directly from hard disk drives. and most HBUILD6 packages packages include an 4P-ROM. If ordering one of those packages, you don't need to order the 4P-ROM separately. Read about HBUILD6 here.

What hard disk drives the 4P-ROM is to be used with	Part Number	Price
4P-ROM ROM for non-gate-array or gate-array Model 4P systems With hard disk driver for Radio Shack WD1000 or TB1 controllers (If you don't have a disk system right now, order this part, as it is the most common controller should you obtain one later on.)	4PBR640	$28.00
4P-ROM ROM for non-gate-array or gate-array Model 4P systems With hard disk driver for MISOSYS SCSI Host interface and Adaptec or XEBEC disk controller	4PBR645	$28.00
4P-ROM ROM for non-gate-array or gate-array Model 4P systems With hard disk driver for non-Radio Shack WD1000 controllers that are port-mapped at 0x78 - 0x7f	4PBR647	$28.00

How to place an order with M. A. D. Software.