Nortel Networks Video Gaming Accessories 553-3001-211 Manual De Usuario

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 NT6D80 MSDL card
Micro Processing Unit (MPU)
The MPU, which is based on a Motorola 68020 processor, coordinates and 
controls data transfer and port addressing, communicating via the CPU bus 
with the system. Prioritized interrupts tell the MPU which tasks to perform.
Memory
The MSDL card contains two megabytes of Random Access Memory (RAM) 
for storing downloaded peripheral software that controls MSDL port 
operations. The MSDL card includes the shared RAM that is used as a 
communication interface buffer between the CPU and the MPU.
The MSDL Flash Erasable Programmable Read Only Memory (Flash 
EPROM) also includes the peripheral software to protect it against a power 
failure or reset. MSDL can copy peripheral software directly from the Flash 
EPROM after power up or reset instead of requesting that the system CPU 
download it.
The MSDL card also contains Programmable Read Only Memory (PROM) 
for firmware that includes the bootstrap code.
Serial interface
The MSDL card provides one monitor port and four programmable serial 
ports that can be configured for the following various interfaces and 
combinations of interfaces:
synchronous ports 0–3
asynchronous port 0
DCE or DTE equipment emulation mode
RS-232 or RS-422 interface
Transmission mode – All four ports of the MSDL can be configured for 
synchronous data transmission by software. Port 0 can be configured for 
asynchronous data transmission for CRT, TTY, and printer applications only.