DMP 1326 & DMP Custom Prox Formats Explained

DMP and Its Access Control Panels

Digital Monitoring Products — universally known as DMP — is a Springfield, Missouri-based manufacturer of intrusion detection, access control, and integrated security panels. The XR Series, XT Series, and 7000 Series panels are deployed across commercial and light-industrial sites throughout North America, and many of those installations rely on proximity credential readers wired back to a DMP controller over a standard Wiegand interface.

Because DMP designs its own panels and firmware, the company has historically offered both a generic credential option and a site-specific custom format intended to reduce cross-site card collision risk. Facilities managers replacing lost cards or onboarding new staff frequently discover that sourcing replacements is not as straightforward as a generic 26-bit card order — particularly when the site was originally programmed with a DMP custom format. That gap is precisely what this guide addresses.

For background on how Wiegand bit structures work across the industry, the Complete Wiegand Format Guide provides a solid foundation before diving into DMP-specific encoding.

DMP 1326: The Standard 26-Bit Card

The DMP 1326 is a standard H10301 26-bit Wiegand proximity card. The format is identical to the ubiquitous 26-bit open format used across hundreds of access control platforms: 1 parity bit, 8 facility-code bits, 16 card-number bits, and 1 trailing parity bit, for a total 26-bit frame transmitted over the Wiegand D0/D1 wire pair. Any reader configured to accept H10301 26-bit credentials will accept a correctly encoded 1326 card.

The practical consequence is that if your DMP installation is running standard 26-bit, the replacement card market is broad. Provided you know your facility code and the card numbers already enrolled in the panel, DMP prox card compatible blanks encoded to H10301 can be ordered in small or large quantities. Readers do not distinguish between an original DMP-branded 1326 and a correctly encoded compatible card — the panel sees identical Wiegand data either way.

A note on card collision: 26-bit H10301 supports only 255 facility codes and 65,535 card numbers per facility code. Sites that began as small installations sometimes encounter duplicate card numbers when they expand. If your DMP panel is still on 26-bit and you are adding many new credentials, it is worth confirming with your integrator whether migration to a longer format is warranted before you place a bulk card order.

The DMP 31-Bit and 33-Bit Custom Proprietary Formats

The more technically involved side of the DMP credential landscape is the proprietary custom format, which appears in both 31-bit and 33-bit variants. These formats were introduced to give DMP installations a larger card-number space and a reduced probability of cross-site credential overlap compared with the saturated 26-bit market. The bit layout differs meaningfully from H10301: facility code and card number fields occupy different bit positions, parity is calculated differently, and the total frame length means a reader not configured for the DMP custom format will either reject the card or misread it.

The 31-bit variant allocates a larger facility code field than H10301 allows, supporting a significantly expanded range of facility codes and card numbers within a single installation. The 33-bit variant extends this further, providing a broader namespace suitable for multi-site enterprise deployments where central credential management is important. Both formats transmit over the same physical Wiegand wire pair as any other LF credential — the difference is entirely in the data structure.

Because these formats are proprietary, they are not stocked by most generic proximity card suppliers. This is why facilities running DMP custom-format sites often face difficulty at the point of card replacement — particularly if the original integrator is no longer engaged or if the site database has been partially lost. The Discontinued and Obsolete Format Card Replacement Service is specifically designed for situations where the original credential source is no longer available. Similar long-tail format challenges appear with Lenel 42-bit compatible cards, Avigilon compatible cards, and Software House CCOTZ 37-bit compatible cards, all of which require format-matched encoding rather than generic blanks.

Encoding a Compatible DMP Card

All DMP LF formats — 26-bit, 31-bit, and 33-bit — are transmitted at 125 kHz using ASK/FSK modulation on a standard proximity chip substrate. The T5577 is the industry-standard programmable 125 kHz chip used for compatible credential production: it can be configured to emulate any LF modulation scheme and bit layout once the target format parameters are correctly specified. For a detailed explanation of how this chip class operates, see T5577 Explained: The Universal 125 kHz Programmable Blank.

Encoding a DMP custom-format card requires three inputs: the target bit length (31 or 33), the facility code assigned to the site, and the card number range to be programmed. Facility codes for DMP custom formats are not the same as the H10301 facility code even if the same numeric value was used — the field width and bit position differ. If you are replacing existing cards, the facility code is typically documented in the access control software database or on the original credential order paperwork. If that documentation is unavailable, reading an existing card with appropriate hardware can recover the facility code value.

Once the format parameters are confirmed, compatible credentials can be produced on standard ISO CR-80 PVC card stock or key fob housings carrying T5577 chips. The resulting DMP proximity card compatible credential presents identical Wiegand data to the panel as the original, so no panel reprogramming is required — enrolled card numbers remain valid.

Ordering Compatible DMP Credentials

Sourcing replacements for a DMP installation begins with identifying which of the three formats — 26-bit H10301, 31-bit custom, or 33-bit custom — is active at your site. The fastest method is to read the Wiegand output of a known-working card with a Wiegand data logger or access control diagnostic tool, then check the bit count and frame structure against the known DMP formats. If you already know your format from installer documentation, the process moves straight to encoding. The How to Identify Your Access Card or Key Fob Format guide walks through this step systematically.

Security ID Systems supplies compatible credentials across the full Wiegand bit-format card range, including all three DMP formats. Orders can be fulfilled in quantities from small departmental top-ups to multi-site volume runs. Credentials are available in standard CR-80 proximity card format, clamshell card format, and key fob formats — all encoded to your specified facility code and card number sequence. For sites that use 125 kHz LF proximity infrastructure broadly, compatible credentials can often be consolidated across a mixed-format estate in a single order.

When placing a DMP custom-format order, supply the bit length (31 or 33), facility code, and the starting and ending card numbers required. If your site also runs adjacent proprietary formats — such as an ADT 31-bit compatible proximity card at a co-located facility — those can be included in the same consignment. Contact the Security ID Systems team to confirm format availability and discuss your site requirements before placing a formal product order.

Security ID Systems is an independent manufacturer and supplier of compatible access-control credentials and is not affiliated with, authorized by, or endorsed by Digital Monitoring Products (DMP).