mk90.commands

Command romtest

Check the full boot ROM and repeated cartridge switching.

Synopsis

romtest

Ordinary invocation: foreground child, PID 3; the shell waits. Not an allowed pipe producer.

Parameters

This command has no documented parameters.

Description

First compares distinct 32-byte markers at byte offsets 0x3FE0, 0x5FE0 and 0x7FE0, reporting 16, 24 and 32 KiB milestones.

Then reads all 128 sectors of the 32 KiB boot ROM and checks the 16-bit word sum. Before each ROM sector it selects the other slot and reads its first byte, exercising slot switching. The final success text is ROM 32K + SWITCH OK.

The operation is read-only and yields between ROM sectors. Use it to diagnose addressing and switching on the already wired 27C256 setup.

Examples

romtest

Limits and side effects

A responsive cartridge in the other slot is required for the switching phase. This does not read all of SMP1, validate its filesystem, prove its capacity or certify electrical timing. Earlier milestone success does not replace the final whole-ROM result.

Status and diagnostics

Success is status 0. Relevant status codes: 1, 13. See the diagnostic reference.