HBCR-2210 Datasheet, PDF (10/15 Pages) Agilent(Hewlett-Packard) – Programmable Bar Code Decode ICs

Parallel Mode Handshake Timing
Handshake and Data Lines
CDY
t_CR
t_CB
t_CS
t_CA
t_CC
CRD
PP0-PP7
Figure 1. Host Commands Received by Decode IC (Reader).
Handshake Timing
t_CR =
t_CB =
t_CS =
t_CA =
t_CC =
Falling edge of command ready to falling edge of command read. Max. = 30 µs for the first byte
of transmission from host.
Falling edge of command read to command valid. Min. = 0 µs
Command valid set up to rising edge of command ready. Min. = 0 µs
Rising edge of command ready to rising edge of command read. Max. = 8 µs
Rising edge of command read to falling edge of command ready. Min. = 0 µs
Handshake and Data Lines
RTS
t_DO
DDY
PP0-PP7
DWR
t_DF
t_DD
t_DA
t_DW
t_DH
Figure 2. Decoder IC Data Sent to Host.
Handshake Timing
t_DO = Falling edge of data ready to data output to bus. Min. = 6 µs Typical Max. = 74 µs
Note: The maximum can be infinite if there is no data to be transmitted. RTS can be used to
determine when there is data. If the scanner is active or escape sequence commands
are being processed, (t_DO = t_DF) can extend by an indefinite amount.
t_DF = Data output to bus to falling edge of data write. Max. = 6 µs
t_DA = Falling edge of data write to rising edge of data ready. Min. = 0 µs
t_DW = Rising edge of data ready to rising edge of data write. Max. = 8 µs
t_DH = Data hold after rising edge of data write. Max. = 4 µs
t_DD = Rising edge of data write to falling edge of data ready. Min. = 0 µs
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