Epson S1C33L03 Laptop User Manual


 
III PERIPHERAL BLOCK: SERIAL INTERFACE
S1C33L03 FUNCTION PART EPSON B-III-8-27
A-1
B-III
SIF
•Ch.2 and Ch.3
For Ch.2 and Ch.3, either port input interrupts or 16-bit timer interrupts are selected, and HSDMA is invoked
by means of those interrupt factor (See Table 8.10).
When port input interrupts are selected, Serial I/F Ch.2 receive buffer full corresponds to port 1, and transmit
buffer empty to port 3. Therefore, HSDMA can be invoked by setting HSDMA Ch.1 and Ch.3 trigger factor
values (D[7:4]/0x40298, D[7:4]/0x40299) of "0011".
Similarly, as Serial I/F Ch.3 receive buffer full corresponds to port 4, and transmit buffer empty to port 6,
HSDMA can be invoked by setting HSDMA Ch.0 and Ch.2 trigger factor values (D[7:4]/0x40298,
D[7:4]/0x40299) of "0100".
When 16-bit timer interrupts are selected, the HSDMA trigger factor set values are different for receive buffer
full and transmit buffer empty.
In the case of Serial I/F Ch.2, receive buffer full corresponds to 16-bit timer 5 compare B, and transmit buffer
empty to 16-bit timer 5 compare A. Therefore, to use HSDMA for both transmission and reception, an
HSDMA Ch.3trigger factor value (D[7:4]/0x40299) of "1001" must be set when the Ch.1 trigger factor value
(D[7:4]/0x40298) has been set to "1000". (HSDMA can also be invoked by the reverse combination of set
values.)
Similarly, to use 16-bit timer 4 compare A and B on Serial I/F Ch.3, HSDMA can be invoked by setting an
HSDMA Ch.2 value of "1001" when the Ch.0 value has been set to "1000". (HSDMA can also be invoked by
the reverse combination of set values.)
With interrupts other than receive buffer full and transmit buffer empty, also, the above approach can be used
to activate the HSDMA channel set for the corresponding port No. or 16-bit timer compare.
Trap vectors
•Ch.0 and Ch.1
The trap-vector address of each default interrupt factor is set as follows:
Ch.0 receive-error interrupt: 0x0C000E0
Ch.0 receive-buffer full interrupt: 0x0C000E4
Ch.0 transmit-buffer empty interrupt: 0x0C000E8
Ch.1 receive-error interrupt: 0x0C000EC
Ch.1 receive-buffer full interrupt: 0x0C000F0
Ch.1 transmit-buffer empty interrupt: 0x0C000F4
The base address of the trap table can be changed using the TTBR register (0x48134 to 0x48137).
•Ch.2 and Ch.3
Ch.2 and Ch.3 do not have dedicated interrupt signals. Either a port input interrupt or 16-bit timer interrupt is
selected, and interrupt handling is performed accordingly.
For details, refer to the "Trap Vector" subsection in the "16-Bit Programmable Timers" or "Input/Output
Ports" section.