CP/M 3 For the ADAM

[RGDiRocco]

## CP/M 3 for the Coleco ADAM — Nino's Latest Progress

Nino has been making some impressive progress on bringing **CP/M 3** to the Coleco ADAM, and his latest updates are starting to show just how much more capable this environment could become.

This isn't simply a matter of getting CP/M 3 to boot on the ADAM. He's been working on the boot loader, BIOS, memory handling, disk support, utilities, and other ADAM-specific requirements needed to make CP/M 3 genuinely useful on the system.

### Native Large-Disk Support

One of the latest milestones is an updated **boot loader and CP/M 3 BIOS with native large-disk support**.

Nino also corrected a problem that was preventing proper "login" when switching between **CP/M 2.2 and CP/M 3 disk types**. The system can now handle both.

To put the large-disk support through a practical test, he configured a disk with a directory capable of handling **512 entries** and filled it with as many small Atari 2600 game files as possible. The Atari files weren't significant themselves—the idea was simply to create enough individual files to thoroughly exercise the enlarged directory.

He then deliberately placed **Zork I at the end of the 1440 disk**.

The result? CP/M 3 successfully reached Zork at the far end of the disk and ran it. It was a clever way of demonstrating that the expanded disk wasn't merely being recognized—the operating system could actually navigate the large directory and retrieve files stored throughout it.

### Expanded Memory and RAM Disk

Another screenshot shows CP/M 3 recognizing a substantially expanded ADAM configuration:

**EXP RAM = 2048K**
**TPA = 44K**
**USER RAM = 1536K**
**RAM DISK M: = 512K**

So we're seeing CP/M 3 working with **2MB of expansion RAM**, with a portion being made available as a **512K M: RAM disk**.

Nino has also developed a RAM-paging probe for determining how much expansion memory is actually installed. In another test configuration, it correctly identifies a **64K expansion**, including detecting the point at which the address space wraps back around rather than mistakenly counting mirrored memory as additional RAM.

That becomes important when software needs to determine the actual memory configuration rather than simply assuming a particular expansion is installed.

### Building CP/M 3 Disks and Data Packs

Another piece of the project is a **CP/M 3 Disk / Datapack Builder**.

The utility shown allows different ADAM configurations to be selected, including the amount of expansion RAM and RAM-disk allocation. It also provides control over the CP/M directory layout and disk size.

That should make creating properly configured CP/M 3 boot media considerably easier than manually assembling everything for a particular ADAM hardware configuration.

### There's Still More to Come

Nino isn't calling the project finished yet.

He still plans to adapt additional **.COM utilities to the ADAM's requirements** and add more of CP/M 3's capabilities, including features such as **date stamps and passwords**.

He's also looking at ADAM-specific control features—including things such as controlling the display colors while running programs like **Zork**.

What we're seeing at this stage is therefore more than simply "CP/M 3 running on an ADAM." The project is gradually becoming an **ADAM-specific CP/M 3 environment**, incorporating the machine's expanded memory, larger modern storage possibilities, and features that weren't part of the ADAM's traditional CP/M setup.

There is still work ahead, but the screenshots demonstrate that some of the important underlying pieces—booting, memory detection, RAM-disk operation, large-disk access, CP/M 2.2/3 disk handling, and large-directory access—are already working.

**More to come as Nino continues development.**