ROM Images

Three sets of ROM images are currently available

ROMs

Name

Roms

IC Description

JDC

IC25 - IC32

From danish vendor JDC

IWS

IC25 - IC29, IC31, IC32

From a model with serial number 820

Hybrid

IC25 - IC27, IC31, IC32

Mix of ROMs from serial numbers 615 and 580

Since I have mainly worked with the JDC ROMs, these are the only ones that have annotation data in their program structures.

Memory

The ROS User’s Manual, figure 1 on page 5, shows the memory layout.

For the JDC ROM image some of this information seems correct, but the address range 0x1000 to 0x17ff is marked as unused. However there is assembler code in this region seemingly related to disk reads.