Initializing The Pts Control Blocks - Intel 8XC196NT User Manual

8XC196NT USER'S MANUAL
INT_PEND1
When hardware detects a pending interrupt, it sets the corresponding bit in the interrupt pending
(INT_PEND or INT_PEND1) registers. When the vector is taken, the hardware clears the pending bit.
Software can generate an interrupt by setting the corresponding interrupt pending bit.
7
NMI EXTINT
Bit
Number
7:6 Any set bit indicates that the corresponding interrupt is pending. The interrupt bit is
4:0 cleared when processing transfers to the corresponding interrupt vector.
The standard interrupt vector locations are as follows:
Bit Mnemonic Interrupt
NMI
EXTINT
RI
TI
SSIO1
SSIO0
CBF
5 Reserved. This bit is undefined.
Figure 5-8. Interrupt Pending 1 (INT_PEND1) Register
5.6

INITIALIZING THE PTS CONTROL BLOCKS

Each PTS interrupt requires a block of data, in register RAM, called the PTS control block
(PTSCB). The PTSCB identifies which PTS microcode routine will be invoked and sets up the
specific parameters for the routine. You must set up the PTSCB for each interrupt source before
enabling the corresponding PTS interrupts.
The address of the first (lowest) PTSCB byte is stored in the PTS vector table in special-purpose
memory (see "Special-purpose Memory" on page 4-6). Figure 5-9 shows the PTSCB for each
PTS mode. Unused PTSCB bytes can be used as extra RAM.
The PTSCB must be located in the internal register file. The location of the
first byte of the PTSCB must be aligned on a quad-word boundary (an address
evenly divisible by 8). Because the PTS uses 16-bit addressing, it cannot
operate across page boundaries. For example, PTSSRC cannot point to a
location on page 05 while PTSDST points to page 00. Both PTSSRC and
PTSDST will operate from the page defined by EP_REG. Write 00H to
EP_REG to select page 00H (see "Accessing Data" on page 4-24).
5-18
— RI
Function
Nonmaskable Interrupt
EXTINT pin
SIO Receive
SIO Transmit
SSIO 1 Transfer
SSIO 0 Transfer
Slave Port Command Buffer Full
NOTE
Address:
Reset State:
TI SSIO1 SSIO0
Standard Vector
FF203EH
FF203CH
FF2038H
FF2036H
FF2034H
FF2032H
FF2030H
0012H
00H
0
CBF