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RE: EPP not working



Hi,

The nDstrobe pulses should be generated automatically when EPP mode
is configured. Data available is indicated with the dav bit in 
R_PAR_X_STATUS (and with an interrupt if it is enabled). 

To enable EPP read you have to set the following i R_PAR0_CONFIG:

ext_mode = 1
enable = on
oe_ack = epp_addr
mode = epp_rd

You also have to make sure that the normal parallel port driver
is disabled (in kernel config) and that the parallel port is
enabled in R_GEN_CONFIG. In arch/cris/kernel/head.S change
the following:

#if defined(CONFIG_ETRAX_PARALLEL_PORT0) || defined(CONFIG_ETRAX_ETHERNET_LPSLAVE)
	; parport 0 enabled using DMA 2/3
	or.w	IO_STATE (R_GEN_CONFIG, par0, select),r0
#endif

into just

or.w	IO_STATE (R_GEN_CONFIG, par0, select),r0

You probably also want to connect the DMA to the parallel port in
R_GEN_CONFIG in the same way.

Regards
/Mikael




-----Original Message-----
From: owner-dev-etrax@xxxxxxx.com]On">mailto:owner-dev-etrax@xxxxxxx.com]On
Behalf Of Eric Tang
Sent: Thursday, December 20, 2001 5:42 AM
To: dev-etrax
Subject: EPP not working


Dear ALL,

	I have got the register references, so i start 
	to test the EPP.
	
	i have set the epp_read mode with ext_mode = 1, and other related
	registers. SO my problem is that if i have set the par0 to
	operate in EPP mode, so it would generate nDstroke pulse
	automatically after i set it to EPP or when i try to 
	read data from STATUS_DATA register?
	i have tested in both cases, i can't see any Stroke pulse coming
	out from par0, so i don't know what 's wrong with it.
	Can anyone help me ?

Regards,
Eric