Spi control register – Rainbow Electronics AT75C220 User Manual
Page 128

AT75C220
128
SPI Control Register
Register Name:SP_CR
Access Type:Write-only
•
SPIEN: SPI Enable
0 = No effect.
1 = Enables the SPI to transfer and receive data.
•
SPIDIS: SPI Disable
0 = No effect.
1 = Disables the SPI.
All pins are set in input mode and no data is received or transmitted.
If a transfer is in progress, the transfer is finished before the SPI is disabled.
If both SPIEN and SPIDIS are equal to one when the control register is written, the SPI is disabled.
•
SWRST: SPI Software reset
0 = No effect.
1 = Resets the SPI.
A software-triggered hardware reset of the SPI interface is performed.
0x20
SP_RPR
Receive Pointer Register
Read/write
0
0x24
SP_RCR
Receive Counter Register
Read/write
0
0x28
SP_TPR
Transmit Pointer Register
Read/write
0
0x2C
SP_TCR
Transmit Counter Register
Read/write
0
0x30
SP_CSR0
Chip Select Register 0
Read/write
0
0x34
–
Reserved
–
–
0x38
–
Reserved
–
–
0x3C
–
Reserved
–
–
31
30
29
28
27
26
25
24
–
–
–
–
–
–
–
–
23
22
21
20
19
18
17
16
–
–
–
–
–
–
–
–
15
14
13
12
11
10
9
8
–
–
–
–
–
–
–
–
7
6
5
4
3
2
1
0
SWRST
–
–
–
–
–
SPIDIS
SPIEN
Table 27. SPI Memory Map (Continued)
Offset
Register Name
Register
Access
Reset Value