Datasheet

C1, C2, C3 BCD-Coded Mode, 0 or 1

KeyA MiFare authentication key A; 6 Bytes hexadecimal coded ASCII-string (16

chars)

KeyB MiFare authentication key B; 6 Bytes hexadecimal coded ASCII-string (16

chars)

Table 10: SKO mode parameter description

Response, if successful:

OK!<CR>

Examples:

Sector 5 which contains block 20 get the keys 112233445566 (key A) and 665544332211

(key B)

STM<SPACE>SKO<SPACE>20<SPACE>112233445566<SPACE>665544332211<C

Possible error codes:

UPA<CR> Unknown parameter

BAE<CR> An unauthenticated block is chosen

KNC<CR> Keys not changeable

UKA<CR> Use Key A for authentication

UKB<CR> Use Key B for authentication

BNR<CR> Block not readable, i.e. wrong key, see Block –and Access Mode

BNA<CR> Block not authenticated, Block No. is not in authenticated sector

NMA<CR> No MiFare 1k or 4k chip authenticated

5.4. Value block Operation (VAL)

This command is used to use the integrated MiFare valueblock operations. A value block is

able to save a signed 4 byte value and one address byte (i.e. own block address). The value

is saved LSB first, i.e. 00000035h written as parameter looks like 35000000h. The value can

be manipulated by four different ways (always depending on access bits). It is usually used

to store information on credit values for e-payment or e-ticketing situations.

There are five different modes for this command:

 Initialization – the first step to use the next operations (sets a initial value/address)

metraTec MiFare Protocol Guide Page 27 of 38