APPENDIX A LIST OF I/O REGISTERS
S1C33L26 TECHNICAL MANUAL
Seiko Epson Corporation
AP-A-39
Register name Address
Bit
Name
Setting
Init. R/W
Remarks
DescDoor
(Descriptor
door)
0x300c8f
(8 bits)
D7–0 DescMode[7:0]
Descriptor door
0x0 R/W
DMA_FIFO_
Control
(DMA FIFO
control)
0x300c90
(8 bits)
D7
FIFO_Running
1 FIFO is running
0 FIFO is not running
0
R
D6
AutoEnShort
1 Auto enable short packet 0 Do nothing
0
R/W
D5–0 –
–
–
–
0 when being read.
DMA_Join
(DMA join
FIFO)
0x300c91
(8 bits)
D7–4 –
–
–
–
0 when being read.
D3
JoinEPdDMA
1 Join EPd to DMA
0 Do nothing
0
R/W
D2
JoinEPcDMA
1 Join EPc to DMA
0 Do nothing
0
R/W
D1
JoinEPbDMA
1 Join EPb to DMA
0 Do nothing
0
R/W
D0
JoinEPaDMA
1 Join EPa to DMA
0 Do nothing
0
R/W
DMA_Control
(DMA control)
0x300c92
(8 bits)
D7
DMA_Running
1 DMA is running
0 DMA is not running
0
R
D6
PDREQ
PDREQ signal logic
0
R
D5
PDACK
PDACK signal logic
0
R
D4
–
–
–
–
0 when being read.
D3
CounterClr
1 Clear DMA counter
0 Do nothing
0
W
D2
–
–
–
–
D1
DMA_Stop
1 Finish DMA
0 Do nothing
0
W
D0
DMA_Go
1 Start DMA
0 Do nothing
0
W
DMA_Config_0
(DMA
configuration 0)
0x300c94
(8 bits)
D7
ActivePort
1 Activate DMA port
0 Disactivate DMA port
0
R/W
D6–4 –
–
–
–
0 when being read.
D3
PDREQ_Level
1 Active-low
0 Active-high
0
R/W
D2
PDACK_Level
1 Active-low
0 Active-high
0
R/W
D1
PDRDWR_Level
1 Active-low
0 Active-high
0
R/W
D0
–
–
–
–
0 when being read.
DMA_Config_1
(DMA
configuration 1)
0x300c95
(8 bits)
D7
RcvLimitMode
1 Receive limit mode
0 Normal
0
R/W
D6–4 –
–
–
–
0 when being read.
D3
SingleWord
1 Single word
0 Multi word
0
R/W
D2–1 –
–
–
–
0 when being read.
D0
CountMode
1 Count-down mode
0 Free-run mode
0
R/W
DMA_Latency
(DMA latency)
0x300c97
(8 bits)
D7–4 –
–
–
–
0 when being read.
D3–0 DMA_Latency[3:0]
Latency
0x0 R/W
DMA_Remain_H
(DMA FIFO
remain high)
0x300c98
(8 bits)
D7–4 –
–
–
–
0 when being read.
D3–0 DMA_Remain[11:8]
DMA FIFO remain
0x0
R
DMA_Remain_L
(DMA FIFO
remain low)
0x300c99
(8 bits)
D7–0 DMA_Remain[7:0]
DMA FIFO remain
0x0
R
DMA_Count_HH
(DMA transfer
byte counter
high/high)
0x300c9c
(8 bits)
D7–0 DMA_Count[31:24]
DMA transfer byte counter
0x0 R/W
DMA_Count_HL
(DMA transfer
byte counter
high/low)
0x300c9d
(8 bits)
D7–0 DMA_Count[23:16]
DMA transfer byte counter
0x0 R/W
DMA_Count_LH
(DMA transfer
byte counter
low/high)
0x300c9e
(8 bits)
D7–0 DMA_Count[15:8]
DMA transfer byte counter
0x0 R/W
DMA_Count_LL
(DMA transfer
byte counter
low/low)
0x300c9f
(8 bits)
D7–0 DMA_Count[7:0]
DMA transfer byte counter
0x0 R/W
0x300e00
Prescaler (PSC)
Register name Address
Bit
Name
Function
Setting
Init. R/W
Remarks
PSC Control
Register
(PSC_CTL)
0x300e00
(8 bits)
D7–2 –
reserved
–
–
–
0 when being read.
D1
PRUND
Prescaler run/stop in debug mode 1 Run
0 Stop
0
R/W
D0
PRUN
Prescaler run/stop control
1 Run
0 Stop
0
R/W
0x301000–0x30100c
Watchdog Timer (WDT)
Register name Address
Bit
Name
Function
Setting
Init. R/W
Remarks
WDT
Write Protect
Register
(WD_
PROTECT)
0x301000
(16 bits)
D15–0 WDPTC
[15:0]
WDT register write protect flag
Writing 0x96 removes the write
protection of the WD_EN, WD_
CMP_L, and WD_CMP_H reg-
isters (0x301002–0x301006).
Writing another value set the
write protection.
X
W 0 when being read.