Cypress CY7C67300 - page 33

CY7C67300
Document #: 38-08015 Rev. *J Page 33 of 99
Register Description
The Host n PID register is a write only register that provides the
PID and Endpoint information to the USB SIE to be used in the
next transaction.
PID Select (Bits [7:4])
The PID Select field is defined in Table54. ACK and NAK tokens
are automatically sent based on settings in the Host n Control
register and do not need to be written in this register.
Endpoint Select (Bits [3:0])
The Endpoint field allows addressing of up to 16 different
endpoints.
Reserved
Write all reserved bits with ’0’.
Host n Count Result Register [R]
■Host 1 Count Result Register 0xC088
■Host 2 Count Result Register 0xC0A8
Register Description
The Host n Count Result register is a read only register that
contains the size difference in bytes between the Host Count
Value specified in the Host n Count register and the last packet
received. If an overflow or underflow condition occurs, that is the
received packet length differs from the value specified in the Host
n Count register, the Length Exception Flag bit in the Host n
Endpoint Status register is set. The value in this register is only
value when the Length Exception Flag bit is set and the Error
Flag bit is not set, both bits are in the Host n Endpoint Status
register.
Result (Bits [15:0])
The Result field contains the differences in bytes between the
received packet and the value specified in the Host n Count
register. If an overflow condition occurs, Result [15:10] is set to
‘111111’, a 2 ’s c o m p le m e n t v al u e i n d i ca t i n g t h e a d d i t i o na l b y t e
count of the received packet. If an underflow condition occurs,
Result [15:0] indicates the excess bytes count (number of bytes
not used).
Reserved
Write all reserved bits with ’0’.
Table 54. PID Select Definition
PID TYPE PID Select [7:4]
SETUP 1101 (D Hex)
IN 1001 (9 Hex)
OUT 0001 (1 Hex)
SOF 0101 (5 Hex)
PREAMBLE 1100 (C Hex)
NAK 1010 (A Hex)
STALL 1110 (E Hex)
DATA0 0011 (3 Hex)
DATA1 1011 (B Hex)
Table 55. Host n Count Result Register
Bit # 15 14 13 12 11 10 9 8
Field Result...
Read/Write RRRRRRRR
Default 00000000
Bit # 76543210
Field ...Result
Read/Write RRRRRRRR
Default 00000000
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