User guide

48 DC 900-1338I

Protocol Software Toolkit Programmer Guide

2.6.2 Programming the Serial Communications Controllers

Four or eight Z8530 or Z85230 serial communications controllers (SCCs) are used to

control the ICP6000’s eight or sixteen ports. Each SCC has two channels, A and B, and

each channel controls transmit and receive operations for one port. For example,

SCC01 controls port 0 on channel A and port 1 on channel B, SCC23 controls port 2 on

channel A and port 3 on channel B, and so on. Tabl e 3–4 on page 55 lists the SCC base

addresses. Each SCC is accessed through the eight-bit registers shown in Tab le 2–7.

Each channel of the SCC contains 16 eight-bit write registers, numbered 0 through 15,

and nine eight-bit read registers, numbered 0, 1, 2, 3, 8, 10, 12, 13, and 15. Write register

Table 2–6: Vector Numbers for SCC Interrupts

Channels

Ve cto r

(Hexadecimal)

0 and 1 40

2 and 3 41

4 and 5 42

6 and 7 43

8 and 9 46

10 and 11 47

12 and 13 4E

14 and 15 4F

Table 2–7: SCC Access Registers

Offset from SCC

Base Address

Channel A Data 0

Channel A Control 1

Channel B Data 2

Channel B Control 3