Epson S1C33210 - Manual (Page 385)

III PERIPHERAL BLOCK: INPUT/OUTPUT PORTS
S1C33210 FUNCTION PART EPSON B-III-9-23
RP3–RP0: Port input 3–0 IDMA request (D[3:0]) /
Port input 0–3, high-speed DMA, 16-bit timer 0 IDMA request register (0x40290)
RP7–RP4: Port input 7–4 IDMA request (D[7:4]) /
Serial I/F Ch.1, A/D, Port input 4–7 IDMA request register (0x40293)
Specifies whether to invoke IDMA when an interrupt factor occurs.
When using the set-only method (default)
Write "1": IDMA request
Write "0": Not changed
Read: Valid
When using the read/write method
Write "1": IDMA request
Write "0": Interrupt request
Read: Valid
RP7 to RP0 are IDMA request bits corresponding to the port-input 7 to 0 interrupts, respectively. If the bit is set to
"1", IDMA is invoked when an interrupt factor occurs, thereby performing a programmed data transfer. If the bit is
set to "0", normal interrupt processing is performed, without invoking IDMA.
For details on IDMA, refer to "IDMA (Intelligent DMA)".
At initial reset, RP set to "0" (interrupt request).
DEP3–DEP0: Port input 3–0 IDMA enable (D[3:0]) /
Port input 0–3, high-speed DMA, 16-bit timer 0 IDMA enable register (0x40294)
DEP7–DEP4: Port input 7–4 IDMA enable (D[7:4]) /
Serial I/F Ch.1, A/D, Port input 4–7 IDMA enable register (0x40297)
Enables IDMA transfer by means of an interrupt factor.
When using the set-only method (default)
Write "1": IDMA enabled
Write "0": Not changed
Read: Valid
When using the read/write method
Write "1": IDMA enabled
Write "0": IDMA disabled
Read: Valid
If DEP is set to "1", the IDMA request by the interrupt factor is enabled. If the register bit is set to "0", the IDMA
request is disabled.
After an initial reset, DEP is set to "0" (IDMA disabled).
Programming Notes
(1) After an initial reset, the interrupt factor flags become indeterminate. To prevent generation of an unwanted
interrupt or IDMA request, be sure to reset the flags in a program.
(2) To prevent regeneration of interrupts due to the same factor following the occurrence of an interrupt, always be
sure to reset the interrupt factor flag before resetting the PSR or executing the reti instruction.
(3) The S1C33210 maps the mobile access interface interrupt request outputs CP[4:0] to port interrupt requests.
To use these interrupts, select them in port input interrupt select registers 1 and 2 (0x00402C6 and 0x00402C7)
and configure them for High level active operation by setting the corresponding bits in the port input interrupt
input polarity input select (0x00402C8) and port input interrupt edge/level select (0x00402C9) registers to "1"
and "0", respectively.
(4) Port operation requires that the prescaler be operating.