The first four bytes, Base+0 through Base+3, of address space on the MPA-200 contain the internal registers of the SCC. The next two locations Base+4 and Base+5 contain the communications register and the configuration register. The last two address port locations are reserved for future use. The entire address range of the MPA-200 is shown in Table 12.

Table 12 MPA-200 Address Assignments

Address

Register Description

 

 

Base + 0

SCC Data Port, Channel A

 

 

Base + 1

SCC Control Port, Channel A

Base + 2

SCC Data Port, Channel B

 

 

Base + 3

SCC Control Port, Channel B

 

 

Base + 4

Communications Register

 

 

Base + 5

Configuration Register

 

 

Base + 6

Reserved

Base + 7

Reserved

 

 

Information on the internal registers of the SCC can be found in the chapter titled SCC GENERAL INFORMATION starting on page 4. The two onboard registers give the user additional options pertaining to DMA, and Interrupts. Information on the configuration register and the communications register can be found in the chapters CONFIGURATION REGISTER on page 21, and COMMUNICATIONS REGISTER on page 23.

Quatech Inc., MPA-200/300 Manual

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Quatech MPA-200/300, RS-422/485 user manual