Changes between Version 16 and Version 17 of TBR/BSP/Mbx860_002

Timestamp:

12/17/11 02:42:48 (12 years ago)

Author:

Ivaylo

Comment:

/* Flash Memory */

TBR/BSP/Mbx860_002

@@ -29 +29 @@
 = Flash Memory =
 
+
+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.
 = IO =