Read Application Note 001 text version

Application Note 002

HID CORPORATION

HID Clock-and-Data Reader Output

5368 5398 6008

HID Corporation's Clock-and-Data readers (model numbers 5368, 5398, and 6008) emulate Magstripe Track II data output. This allows for easy upgrade from magstripe to proximity.

Standard Magnetic Stripe Track II Reader Output

The magnetic stripe track II output that the Clock-and-data readers emulate is shown below in figure 1. The message is a character wise message and consists of 25 leading zeros, a start sentinel B, data characters, end sentinel F, Longitudinal Redundancy Check (LRC), and 165 trailing zeros.

< 25 leading 0's> B <data characters> F (LRC) < 165 trailing zeros > B = Start character F = Stop Character LRC = Longitudinal redundancy check FIGURE 1 Each character represents five bits consisting of four data bits and one odd parity bit as shown here. ddddp xxxxo d = data bit, p = odd parity, x = parity mask

Example: Start character B would look like the following, B 10110 ddddp xxxxo 1248 = LSB.....MSB

E. Sprik AN002f.doc 9/21/1998

Page 1

Interpretation of Clock-and-data Reader Output Cont'd

Clock-anddata Interface

The HID Clock-and-data reader interface emulates a magnetic stripe track II reader output. The timing diagram is shown below in figure 2. This consists of three signals ­ card present, clock (strobe), and data. The card present signal must go low before the start of data transmission. It will remain low while data is transferred and return to high after transmission is complete. The clock (strobe) signal synchronizes the host system with the reader enabling data to be sent and received properly. The data signal sends the encoded data to the host. This is a negative edge triggered signal. Low signals are interpreted as 1's and high signals as 0's. CLOCK & DATA INTERFACE PULSES

Card Present

data

0

0

0

0

0

0

0

0

0

0

0

0

50mS max

1 clock/ strobe

1

1

1

1

1

1

1

1st valid bit

bit time

strobe width

Note: the first 25 bits and trailing bits are zeros, not shown above. · bit time = 1.5ms (default) · strobe width = bit time/3 (33% of bit time), default = 500µs · clock/strobe is valid 1.5ms (one clock cycle, min) after card present is asserted · data is valid 10µs (min) before the negative edge of clock/strobe · card present returns to the high level 50 ms (max.) after the last clock/strobe.

FIGURE 2

Clock-and-data Reader Output of Standard Wiegand Formatted HID Cards

By E. Sprik AN002f.DOC 9/21/1998

When a standard, Wiegand formatted HID card is read on a Clock-and-data Reader, data is sent to the host in the following manner:

Page 2

Interpretation of Clock-and-data Reader Output Cont'd

<25 leading zeros> B DDDD DDDD DDDD DDDD F (LRC)<trailing zeros> D = 16 data characters The character data (D) is packed into groups of three bits (octal), and sent to the host as a 16 character message. The conversion of binary card data to reader output character data is shown below. Binary card data = a bcd efg hij klm nop qrs tuv wxy zAB CDE FGH IJK. The Reader converts the card data to five bit groups by reversing the bit order, adding a filling zero and parity to the right side of each group, and sends it to the Host. 1248p 1248p 1248p 1248p 1248p 1248p 1248p.......1248p 1248p 1248p <B> 0000p 0000p 0000p a000p dcbop gfe0p ....... KJI0p <F> <LRC>

HID 37 Bit Clock and Data card Format H10320

The 37 bit Clock-and-data card format (H10320) is designed to be used with the Clock-and-Data reader. The format is shown below. The card data is Binary Coded Decimal (BCD). This differs from standard Wiegand formatted cards which are encoded with binary data. The 32 bit A field is sent as an 8 character Magnetic Stripe (MS) track II message.

1A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A P P P P X X X X X X X X E X X X X X X X X O X X X X X X X X E X X X X X X X X E

1 = set bit A = Card number, 32 bits, range = 0 to 99,999,999

P = Parity even and odd X = Parity mask

Clock-and-data Reader Output of Clock-and-data H10320 Formatted Cards

When a Clock-and-data card is presented to a HID Clock-and-data reader, the output is as shown below.

<25 leading 0's> B D D D D D D D D F (LRC) < 165 trailing zeros >

By E. Sprik AN002f.DOC 9/21/1998

Page 3

Interpretation of Clock-and-data Reader Output Cont'd

D = Eight characters of data. Each character is 4 bits of BCD (4 bits per character X 8 characters = 32 bit card number) Card Range: 0 to 99,999,999 Example 1: card number = 0 <25 leading 0's> B 0 0 0 0 0 0 0 0 F (165) Example 2: card number decimal 99,999,999 <25 leading 0's> B 9 9 9 9 9 9 9 9 F (165)

Conversion of Clock-and-data Reader Output of Standard Format Cards Back to the Standard Wiegand Data Structure

The Clock-and-data reader can also read a standard Wiegand formatted HID card. But the character data must be manipulated before it will make any sense to the panel, or to the user.

To convert the data back into a standard card format: Step 1 Drop the <25 leading zeros>, start (B) character, stop (F) character , LRC, and trailing zeros. Step 2 Starting on the right (least significant bit), convert the octal data characters into the equivalent 3 bit binary groups. Drop all bits above the last format bit (i.e. Anything above bit 26 in a 26 bit format). Step 3 Strip off the parity bits. In standard card formats the parity bits are the first and last bit. Example: remove bit 1 and bit 26 in a 26 bit format. pddddddddddddddddddddddddp. p= parity bit and d= 24 data bits. Step 4 Regroup the remaining binary data into four bit binary sets starting on the right hand side with the least significant bit. Step 5 Separate the characters based on the different facility code and card number fields. Step 6 Convert the hex characters in each field to the equivalent decimal number. The standard 26 bit Wiegand format is H10301. It is Standard 26 Bit binary encoded data. The format consists of 2 parity Format Structure bits, 8 bit facility code and 16 bit card number fields. The format is shown below. PAAAAAAAABBBBBBBBBBBBBBBBP EXXXXXXXXXXXX XXXXXXXXXXXXO

By E. Sprik AN002f.DOC 9/21/1998 Page 4

Interpretation of Clock-and-data Reader Output Cont'd

P = Parity A = Facility code, range = 0 to 255 B = Card Number, range = 0 to 65,535

O = Odd Parity E = Even Parity X = Parity mask

Example : Conversion of Clock-and-data to Standard 26 Bit Output

The conversion of the clock and data reader output of a 26 bit formatted card back to standard encoded data is shown below.

The Clock-and-data reader will output the data in the character format shown in the previous sections. For the 26 bit format the leading characters will be zeros. The first non zero character contains the start sentinel (this is the first one bit). The start sentinel is at bit 27 for 26 bit cards. All bits following the start sentinel are pertinent card data. In this case it is 26 bits of data. Example: 26 bit format H10301, facility code = 5, card number = 8 The Clock-and-data reader will output the following: <25 leading 0's> B 0000 0004 0240 0020 F < 165 trailing zeros>

Step 1 Drop the <25 leading zeros>, start (B) character, stop (F) character , LRC, and trailing zeros. This leaves the following 9 characters of octal data. 402400020

Step 2 Starting on the right (least significant bit), convert the octal data characters into the equivalent 3 bit binary groups. Drop all bits above bit 26. 0 2 4 0 0 0 2 0 00 000 010 100 000 000 000 010 000 pd ddd ddd ddd ddd ddd ddd ddd ddp Step 3 Strip off the parity bits. There should be 24 bits remaining. 000001010000000000001000= 24 bits

By E. Sprik AN002f.DOC 9/21/1998 Page 5

Interpretation of Clock-and-data Reader Output Cont'd

dddddddddddddddddddddddd

Step 4 Regroup the remaining binary data into four bit binary sets starting on the right hand side with the least significant bit. 0000 0101 0000 0000 0000 1000 dddd dddd dddd dddd dddd dddd Step 5 Separate the characters based on the different facility code and card number fields. | facility | card | | code | number | 0000 0101 0000 0000 0000 1000 f f f f f f f f cccc cccc cccc cccc The first 2 hex characters represent the facility code (f) while the last 4 hex characters represent the card number (c). Step 6 Convert the hex characters in each field into the equivalent decimal number. 0000 0101 0000 0000 0000 1000 f f f f f f f f cccc cccc cccc cccc 0 5 0 0 0 8 The numbers in the facility code and card number fields will be the same as the standard HID Wiegand reader will report. 0 5 = eight bit Facility Code = 5 decimal 0 0 0 0 8 = sixteen bit Card Number = 8 decimal

37 Bit Format (H10302) Structure

The HID 37 bit Wiegand format is H10302. It is binary encoded data. The format is shown below.

PAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAP EXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXO Where P = Parity

By E. Sprik AN002f.DOC 9/21/1998 Page 6

O = Odd Parity

Interpretation of Clock-and-data Reader Output Cont'd

A = Card Number, range = 0 to 34,359,738,367

E = Even Parity

Example: Conversion Clock-and-data to 37 Bit Format (H10302)

The conversion of a 37 bit formatted card's output on a Clock-and-data reader is similar to the previous 26 bit card conversion example.

Example: Standard 37 bit format (H10302), card number = 12,120 The character output sent from the reader will look like the following. <25 leading 0's> B 0000000000057261F < 165 trailing zeros > To convert the data back into the form of a standard Wiegand card format several steps must be taken. Step 1 Drop the <25 leading zeros>, start (B) character, stop (F) character , LRC, and trailing zeros. 0000000000057261

Step 2 Starting on the right (least significant bit), convert the octal data characters into the equivalent 3 bit binary groups. Drop all bits above bit 37. 0 0 0 0 0 0 0 5 7 2 6 1 0 000 000 000 000 000 000 000 101 111 010 110 001 p ddd ddd ddd ddd ddd ddd ddd ddd ddd ddd ddd ddp

Step 3 Strip off the parity bits. There should be 35 bits of data remaining. 000 000 000 000 000 000 000 101 111 010 110 00 ddd ddd ddd ddd ddd ddd ddd ddd ddd ddd ddd dd Step 4 Regroup the remaining binary data into 4 bit binary sets starting on the right hand side with the least significant bit. 000 0000 0000 0000 0000 0010 1111 0101 1000 ddd dddd dddd dddd dddd dddd dddd dddd dddd

By E. Sprik AN002f.DOC 9/21/1998

Page 7

Interpretation of Clock-and-data Reader Output Cont'd

Step 5 Separate the characters based on the different facility code and card number fields. Since the Standard HID 37 bit format (H10302) only has a card number field (c), this step is not needed. There is no Facility Code. 0 0 0 2 F 5 8 0000 0000 0000 0010 1111 0101 1000 cccc cccc cccc cccc cccc cccc cccc Step 6 Convert the hex characters in each field to the equivalent decimal number. 2F58 hex = 12,120 decimal The final data is a 37 bit formatted card (H10302) with a decimal card number of 12,120.

By E. Sprik AN002f.DOC 9/21/1998

Page 8

Information

Application Note 001

8 pages

Find more like this

Report File (DMCA)

Our content is added by our users. We aim to remove reported files within 1 working day. Please use this link to notify us:

Report this file as copyright or inappropriate

742700


You might also be interested in

BETA
NB500/NB505/NB520/NB525/NB550D/NB555D Series User's Manual
Neuron Chip TMPN3150/3120
Alternative Reader Wiring Guide
User's Manual