User Manual

CIRCUIT ANALYSIS
• DRAM Circuits U2 & U7 • Flash Circuits U10 & U11
6.9.1 DRAM
Two 128-Mbit, 16 bit wide synchronous DRAM Integrated Circuit modules U2 and U7
are organized in a 4M x 32 configuration. These two modules provide a minimum of 16
Mbytes of storage, upgradeable to 64 Mbytes. The following table shows the MPC860P
bank addresses for the different DRAM memory sizes.
Table 8 - DRAM Bank Memory Ranges
Bank 64-Mbit (DRAM) 128-Mbit (2xDRAM) 256-Mbit (SDRAM)
Bank 1 0x003FFFFF – 0x00000000 0x003FFFFF – 0x00000000
0x013FFFFF – 0x01000000
0x003FFFFF – 0x00000000
0x013FFFFF – 0x01000000
0x023FFFFF – 0x02000000
0x033FFFFF – 0x03000000
Bank 2 0x007FFFFF – 0x00400000 0x007FFFFF – 0x00400000
0x017FFFFF – 0x01400000
0x007FFFFF – 0x00400000
0x017FFFFF – 0x01400000
0x027FFFFF – 0x02400000
0x037FFFFF – 0x03400000
Bank 3 0x00BFFFFF – 0x00800000 0x00BFFFFF – 0x00800000
0x01BFFFFF – 0x01800000
0x00BFFFFF – 0x00800000
0x01BFFFFF – 0x01800000
0x02BFFFFF – 0x02800000
0x03BFFFFF – 0x03800000
Bank 4 0x00FFFFFF – 0x00C00000 0x00FFFFFF – 0x00C00000
0x01FFFFFF – 0x01C00000
0x00FFFFFF – 0x00C00000
0x01FFFFFF – 0x01C00000
0x02FFFFFF – 0x02C00000
0x03FFFFFF – 0x03C00000
6.9.2 FLASH
Two flash memory modules U10 and U11 are organized as 1M x 32 for non-volatile
program storage (Flash). These two modules have 4 Mbytes of flash memory with the
ability of expansion up to 8 Mbytes. The program execution takes place directly from
flash so that performance is as important as is the ability to load new code while in the
lab and while in the field.
6.9.3 Quad UART
The QUART circuit for the Controller Board is shown on Schematic Diagram WD-
CB101069V1, Sheet 17.
Universal Asynchronous Receiver-Transmitter (UART) U28 is used to handle
asynchronous serial data communication. Asynchronous means that the data is not
synchronous, that is, it is not occurring at a steady constant rate, but is being transmitted
intermittently through serial ports. In data transmission, serial means, transmitting one
bit at a time.
The serial port is a general-purpose interface that conforms to the Recommended
Standard–232C (RS-232C) and can be used to interface with almost any type of device
(modem, mouse and serial printer, etc.).
MM101271V1 R1A 41