ISP1581
Hi-Speed USB peripheral controller
Philips Semiconductors
Table 64: Scratch Information register: bit description
Bit
Symbol
Description
15 to 8
7 to 0
SFIRH[7:0]
SFIRL[7:0]
scratch firmware information register (high byte)
scratch firmware information register (low byte)
9.5.5 Test Mode register (address: 84H)
This 1-byte register allows the firmware to set the (D+, D−) lines to predetermined
states for testing purposes. The bit allocation is given in Table 65.
Remark: Only one bit can be set at a time.
Table 65: Test Mode register: bit allocation
Bit
7
6
5
4
3
PRBS
0
2
1
JSTATE
0
0
Symbol
Reset
FORCEHS
reserved
FORCEFS
KSTATE
SE0_NAK
0
0
-
-
-
-
0
0
0
0
0
0
Bus reset
Access
0
0
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
Table 66: Test Mode Register: bit description
Bit
Symbol
Description
7[1]
FORCEHS
A logic 1 forces the hardware to high-speed mode only and
disables the chirp detection logic.
6 to 5
4[1]
-
reserved.
FORCEFS
A logic 1 forces the physical layer to full-speed mode only and
disables the chirp detection logic.
3[2]
PRBS
A logic 1 sets the (D+, D−) lines to toggle in a pre-determined
random pattern.
2[2]
1[2]
0[2]
KSTATE
JSTATE
Writing a logic 1 sets the (D+, D−) lines to the K state.
Writing a logic 1 sets the (D+, D−) lines to the J state.
SE0_NAK
Writing a logic 1 sets the (D+, D−) lines to a HS quiescent state.
The device only responds to a valid HS IN token with a NAK.
[1] Either FORCEHS or FORCEFS should be set to logic 1 at a time.
[2] Of the four bits (PRBS, KSTATE, JSTATE and SE0_NAK), only one bit must be set to logic 1 at a
time.
10. Power supply
The ISP1581 can be powered from 3.3 V or 5.0 V.
If the ISP1581 is powered from VCC = 5.0 V, an integrated voltage regulator provides
a 3.3 V supply voltage for the internal logic and the USB transceiver. For connection
details, see Figure 6.
The ISP1581 can also be operated from VCC = 3.3 V. In this case, the internal
regulator is disabled and all the supply pins are connected to VCC. For connection
details see Figure 7.
9397 750 13462
© Koninklijke Philips Electronics N.V. 2004. All rights reserved.
Product data
Rev. 06 — 23 December 2004
46 of 79