The Maho 500C has 24 kB of program memory, and the proposed 1 MB card is not a plug-in capacity upgrade unless the control has the required CPU and software compatibility. The available note associates 1 MB card operation with a 10 MHz CPU and software version V600 or later; the machine is reported as software version 6 097/405, so verify the exact control configuration before changing constants or buying upgrade parts.
Compatibility conditions for a Maho 500C 1 MB card
Memory capacity alone does not determine whether the card will be detected. The stated compatibility condition is a 10 MHz CPU with software V600 or later. The owner’s version string, 6 097/405, is not plainly the same notation as V600; treat it as a version identifier to decode with the machine documentation or DMG support, not as confirmation that the threshold is met.
| Decision item | Reported value or condition | Where to verify |
|---|---|---|
| Existing program memory | 24 kB | Control memory display or machine documentation |
| Proposed card capacity | 1 MB | Card label and manufacturer documentation |
| CPU requirement stated for 1 MB card | 10 MHz | CPU identification or machine parts documentation |
| Software threshold stated | V600 or later | Control version display and official version documentation |
| Card part number | Owner: 4022-226-2340; compatibility note: 4022-226-3340
|
Read the card label and confirm the exact part number with DMG |
Card identification before changing constants
The reported card numbers differ in the final digits: 4022-226-2340 and 4022-226-3340. That discrepancy matters because compatibility cannot be transferred from one number to another without confirmation. Read the installed card’s complete part number directly from its label and have the machine’s control configuration checked against that exact number.
The machine owner has no constant legend. That makes guessing a constant unsafe: a constant may control a function unrelated to card recognition, and an unsupported change can create additional machine faults. Obtain the clear-text machine-constant documentation for the specific control/software configuration before editing any value.
Diagnostic path for a card that is not detected
Use the CPU and software configuration as the primary decision points, rather than assuming the machine merely needs a memory-size setting.
- Record the full software version exactly as displayed, including punctuation and suffixes.
- Identify the CPU and verify whether it is the stated 10 MHz type.
- Read the card’s exact part number and capacity from its label.
- Ask DMG to confirm that the exact card, CPU, software version, and machine-constant set are compatible.
- Only after compatibility is confirmed, follow the machine-specific installation and constant procedure.
If the CPU or software does not meet the stated condition, card detection should not be treated as a constants-only problem. The stated upgrade path requires the necessary CPU and software parts; changing constants cannot substitute for missing hardware or software compatibility.
Recommended upgrade route and limits
The recommended route is to establish the exact parts and version first, then obtain official documentation for the machine constants and any required upgrade. The available technical note identifies CPU and software as necessary upgrade components but does not provide a constant number, a card installation sequence, or a method for updating software. Do not infer those details from the card capacity.
Ask the machine manufacturer or authorized service channel for the clear-text constants applicable to the exact control version, confirmation of card part-number compatibility, and a bill of required CPU/software parts if an upgrade is needed. An upgrade is only practical when those required parts and software are available for the machine.
Verification after an approved installation
After following the machine-specific procedure, verify that the control identifies the card and reports usable memory as described in its documentation. Then test a representative program transfer and confirm that the control can store and retrieve the program. Preserve the original constant values and document any authorized changes so the machine can be restored if the result differs from the expected behavior.
Stop before editing undocumented constants or installing an unverified card. Escalate to official DMG support when the CPU frequency, version mapping, card part number, constant legend, or required upgrade parts cannot be confirmed.
FAQ
Why does my Maho 500C not detect a 1 MB memory card?
The stated compatibility condition is a 10 MHz CPU and software V600 or later. Verify the CPU, exact software version, and card part number before investigating constants.
Why are there two different Maho memory card part numbers?
The reported numbers are 4022-226-2340 and 4022-226-3340. Read the card label and have DMG confirm compatibility for that exact number.
Can I change a machine constant to make the card work?
Do not guess a constant when the machine has no constant legend. Obtain the clear-text constants for the exact control configuration and confirm CPU/software compatibility first; stop and escalate to official support if any of those identifiers remain uncertain.