Greenspring P2 Video Graphics Controller

Performance and Application Panorama of Greenspring P2 Video Graphics Controller

The performance and stability of graphic display are crucial in embedded industrial computing and military systems. Greenspring P2 Video is a single width Type II module based on the PC/MIP (PCI Mezzanine Card Industrial Package) standard, designed specifically for systems that require efficient CRT and LCD video graphics output. Although it has been discontinued, it still has significant continued use value in specific industrial, communication, and military equipment. This article will provide a comprehensive technical analysis of the module from multiple dimensions, including hardware architecture, graphics performance, interface design, compatibility, power consumption and size, supporting products, and application scenarios.

Product positioning and market background

P2 Video is a video graphics controller module that uses Silicon Motion Lynx EM4 graphics processor and supports CRT and LCD display output. Its maximum resolution is 1024 × 768 pixels, with a refresh rate of up to 75Hz, and a color depth of up to 24 bits per pixel (bpp), making it stable on a single display device. This module is mainly used for systems that require embedded graphics output, such as industrial consoles, communication equipment, medical imaging terminals, and military display and control systems.

Due to its compliance with the PC/MIP 0.9 draft specification and PCI 2.1 specification, P2 Video has good modular compatibility and can be inserted into designated slots of various carrier boards (such as MC-101, MC-303, MC-606, MC-607, MIC-804, etc.). It is particularly important to note that if the bus master function of the graphics controller is enabled, it must be installed in the slots that support bus master, which are highlighted in bold in the carrier manual.

Core hardware architecture

1. Graphics Processing Unit and Video Memory

The core of P2 Video is the Silicon Motion Lynx EM4 graphics controller, which is an efficient GPU designed specifically for embedded systems, supporting hardware acceleration and BitBit (block transfer) functionality. Although the "Hardware acceleration and BitBit" field repeatedly appears in the document, it actually emphasizes the module's efficient capabilities in graphic drawing, bitmap movement, and window rendering.

In terms of video memory, the module is equipped with 4 Mbytes of SGRAM (Synchronous Graphics Random Access Memory) and a bus width of 128 bits. Although this graphics memory configuration cannot be compared to modern GPUs, it can still ensure smooth graphics output at 1024 × 768 resolution and 24 bit color depth. The high bandwidth characteristics of SGRAM are particularly suitable for common window systems, graphical interfaces, and control panel displays in embedded systems.

2. Interface and Front end I/O

The front panel of P2 Video is equipped with a high-density DB15 CRT connector, which is used to directly connect CRT displays or connect LCD displays through adapters. It is worth noting that the module does not provide additional flexible I/O interfaces (Flexible I/O is "none"), indicating that its design goal is clear: to focus on standard VGA/SVGA output without expanding other video or control signals.

The onboard oscillator frequency is 14.31818 MHz, which is the standard frequency generated by VGA timing to ensure compatibility with various display devices.

Display resolution and refresh rate support

P2 Video supports multiple standard resolution and refresh rate combinations, covering 8-bit, 16 bit, and 24 bit color depths. The following are the specific supported display modes:

640 × 480: Supports 8, 16, 24 bpp, refresh rates of 60, 75, 85 Hz

800 × 600: Supports 8, 16, 24 bpp, refresh rates of 60, 75, 85 Hz

1024 × 768: Supports 16 and 24 bpp, refresh rates of 60 and 75 Hz

It should be noted that 8-bit color depth mode is not supported at a resolution of 1024 × 768, which may be due to memory bandwidth or internal limitations of the controller. But 16 bit and 24 bit color depth are sufficient to meet the needs of most industrial and military applications for graphical interfaces, icons, charts, and video playback.

The highest refresh rate is 75Hz (at a resolution of 1024 × 768), which is smooth enough for non dynamic video scenes such as HMI human-machine interfaces. For applications that require higher refresh rates, it is recommended to reduce the resolution to 800 × 600 or 640 × 480.

Physical dimensions and environmental adaptability

P2 Video adopts the PC/MIP single width Type II 10H external specification, and the module has a "porch" structure with front-end I/O interface. Its size is 47.0mm (height) x 99.0mm (length), and its weight is only 0.04kg (approximately 0.085 pounds), making it very suitable for embedded systems with limited space.

Power requirements:

+3.3 VDC: Maximum 150 mA

+5 VDC: Maximum 10 mA

The overall power consumption is extremely low (less than 0.5W), and there is no need for active cooling, making it suitable for fanless designs.

Environmental parameters:

Working temperature: 0 ° C to 70 ° C

Storage temperature: -40 ° C to+85 ° C

Humidity: 5% to 95%, non condensing

This temperature range covers most commercial and industrial environments, but if it needs to be extended to military grade applications below -40 ° C, additional evaluation is required.

Compatibility and Carrier Slot Strategy

P2 Video, as a Type II module, can be inserted into any Type II module site. But if using the bus master control function of the graphics controller (such as DMA transfer, hardware cursor, video acceleration, etc.), it must be installed in a slot that supports bus master control. The following is the compatibility table of the carrier board and slot provided in the document:

Carrier board model type supports bus master control slots

MC-101 Short PCI (all PCI slots)

MC-303 3U CompactPCI 4, 5

MC-606 6U CompactPCI 4, 5, 6, 7

MC-607 6U CompactPCI 4, 5, 6, 7

MIC-804 Long PCI 4, 5, 6, 7

In addition, the document specifically states that Type II modules can only be accepted in slots 5, 6, and 7 of the MC-804 carrier board when additional height is available. This indicates that there may be mechanical height limitations in these slots, which need to be confirmed in advance when designing integration.

Supporting products and engineering kits

1. Engineering kit (EK-P-VIDEO)

For the convenience of engineers to quickly integrate, the manufacturer provides the P2 Video engineering kit, which includes the following contents:

Printed Hardware User Manual

Bill of Materials (BOM)

assembly drawing

Floppy disk, containing:

Windows NT 4.0 Drivers

Control panel mini program

In addition, a Silicon Motion Lynx EM710 user manual can be provided according to demand.

2. Related products

PMC-VIDEOPLUS: Another PMC standard module that supports SVGA/CRT display, with a maximum resolution of 1280 × 1024 and higher performance.

B-004: Front panel baffle, suitable for single width Type II 10H modules, supports DB9 or HD15 connectors.

Application scenarios and continued use value

Although P2 Video has been discontinued, independent suppliers such as Artisan Technology Group are still providing "second-hand and in good condition" inventory equipment, and supporting services such as emergency procurement, repair, and surplus equipment recycling. This provides valuable lifecycle extension tools for organizations that are still using outdated systems.

Typical application scenarios include:

Industrial control systems: such as old CNC machine tools, PLC human-machine interfaces, HMI workstations.

Communication equipment: such as local display output of microwave stations and base station consoles.

Medical imaging terminals: Some early ultrasound and endoscopic systems still rely on such standard graphics modules.

Military display and control systems, such as radar terminals and command consoles, require long-term stability, low power consumption, and wide temperature adaptability.

Technical limitations and development suggestions

P2 Video represented a high level of embedded graphics when it was released, but by modern standards, its limitations are evident, such as small memory capacity (4MB), lack of support for high-definition resolutions (1080p or higher), and absence of digital video interfaces (such as DVI, HDMI). It is recommended to continue using it in the following situations:

The system cannot change the structure of the carrier board or backplane

Software drivers depend on Windows NT 4.0 or specific graphics APIs

Due to limited project budget, it is not possible to fully upgrade to PCIe or VPX architecture

If an upgrade is needed, PMC-VIDEOPLUS or other modern PC-MIP modules that support higher resolution, larger VRAM, and multiple display outputs can be considered.