|Board Name||MBX860 005b|
|CPU Model||MPC860 40MHZ|
|Runs on Simulator?||No.|
|RAM||16MB Parity DRAM|
|Non-volatile Memory||One bank 32-bit Flash (2MB, 4MB, or 8MB)|
|Serial Ports||Two additional EIA-232-D serial ports|
Motorola MBX860 005b
- 16MB Parity DRAM
- 4MB Flash
- auxiliary ports
MBX860 models include:
- 40 MHz MPC860 processor
- 10BaseT Ethernet
- EIDEand Floppy interfaces
- 32KB NVRAM
- keyboard, mouse, IR, COM1 and COM2 ports
- COMM interface connector
The MPC860 processor is especially well-suited for applications involving communications and networking systems. The CPU on the MPC860 is a 32-bit PowerPC™ implementation incorporating memory management units (MMUs) and instruction/data caches.It has a communications processor module that includes an Interprocessor-Integrated Controller (I2C) channel for data exchanges between the MPC860 and other ICs with I2C capability — microcontrollers, LCD displays, real-time clock devices, etc. The MPC860’s memory controller supports all available types of memory. Its PCMCIA controller supports up to two PCMCIA sockets (one is implemented on the MBX) and a real-time clock.
The MBX series embedded controller has provision for either 4MB or 16MB of on-board DRAM, soldered in place. In addition, it accommodates 8MB to 64MB of expansion DRAM in a 168-pin DIMM (dual in-line memory module) socket, XU3. The on-board DRAM is composed of two 16-bit devices (either 1M x 16 or 4M x 16). Parity protection is optional. If expansion DRAM is installed in the DIMM socket, it must have the same characteristics as the on-board DRAM: single bank, 3.3V,EDO (extended data out), 4K refresh rate, and same clock speed.
Flash memory on the MBX series embedded controller consists of 2MB (on entry-level versions) or 4MB (on standard versions) of EPPCBug firmware resident in one bank of four devices soldered directly to the board. The firmware resident in Flash memory is originally loaded at the factory, but the Flash contents can be reprogrammed if necessary.
The on-board monitor/debugger, EPPCBug, resides in the Flash chips. The EPPCBug firmware provides functionality for:
- Booting and resetting the system
- Initializing a request
- Displaying and modifying configuration variables
- Running self-tests and diagnostics
- Updating firmware ROM
For purposes of reprogramming Flash, the MBX includes a 32-pin socket (XU2) in which firmware programmers can install a removable boot ROM device. A jumper header (J4) enables you to select either the on-board Flash memory or the socketed Flash chip in XU2 as the boot ROM. Depending on the configuration of J4,resets execute either from the on-board Flash memory bank (32-bit Flash) or from the socketed boot ROM (8-bit Flash).
In normal operation, the Flash devices are in “read-only” mode,their contents are predefined, and they are protected against inadvertent writes arising from power outages. However, for programming purposes, programming voltage is always supplied to the devices and the Flash contents may be modified by executing the proper program command sequence. Refer to the third-party data sheet and/or to the PowerPC EPPCBug Firmware Package User’s Manual for further device-specific information on modifying Flash contents.
The MBX series embedded controller uses a 37C672 Super I/O controller chip from Standard Microsystems to implement the onboard peripheral functions of the standard version:
- An asynchronous serial port (COM1) for the console/terminal interface
- IEEE1284 bidirectional parallel port
- Floppy disk drive support
- Keyboard and mouse interface
The MBX series embedded controller accommodates 32KB of nonvolatile RAM (NVRAM) in a 34-pin socket, XU1. A battery supplies Vcc to the NVRAM when main power is removed. The NVRAM provides for a low-battery indication which can be read by the MPC8xx processor (via status register #2 — see Programmer's Reference Guide) so that you can replace the battery before it discharges completely.
The on-board backup power source for the NVRAM is a Sanyo CR14250SE lithium battery which is socketed for easy removal and replacement. A small capacitor is provided to allow the battery to be quickly replaced without data loss.
The lifetime of the battery is very dependent on the ambient temperature of the board and the power-on duty cycle. At 70°C, the worst-case elapsed time for battery protection is 7 years. Battery warning time is 24 hours minimum. At lower ambient temperatures the backup time is greatly extended.
When a board is stored, the battery should be disconnected to prolong battery life. This is especially important at high ambient temperatures. The MBX board is shipped with the on-board battery disconnected (i.e., with a jumper installed across J1 pins 2 and 3). If you intend to use the battery as a backup power source, it is necessary to reconfigure the jumpers on J1 and J2 before installing the board. Refer to Backup Power Configuration and Backup Power Conditioning in Chapter 1 for the jumper configurations to use.