Spi Timing - Elatec TWN3 Mini Reader Mifare NFC Technical Manual

The previous image shows the response of the reader, in this case it is the ASCII-representation of the
version string "MifareNFC 1.02<CR><LF>" (with leading length-byte 0x10).

2.5.1 SPI Timing

SPI Interface: Timing requirements. Drawing is not for scale!
1
SS
2
SCK
3 4
MOSI
MSB
MISO
MSB
Marking Description
1 SS ¯¯ low to start of clocking
2 SS ¯¯ low to data output
3 Data input setup time
4 Data input hold time
5 SCK to data output
6 SCK low
7 SCK high
8 SCK rise/fall time
9 SCK period
10 SCK to SS ¯¯ high
11 SS ¯¯ inactive time
12 SS ¯¯ high to tri-state
Please note: The reader requires a boot time of at least 5ms until full SPI functionality is provided. The
boot time is adjustable by the EEPROM to higher values. It is good practice for the master, to issue a
hard reset after power-up while SS
boot time has elapsed, SS
Elatec GmbH
5
Min
5µs
10ns
90ns
182ns
182ns
364ns
4µs
8µs
¯¯ remains inactive and SCK / MOSI have a logic low level. After the
¯¯ may be tied to low for the first time in order to read the version string.
9 10
6 7 8
LSB
LSB X
Typ Max
15ns
15ns
1600ns
10ns
11
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X