From: ian <ian>
Date: Sun, 13 Nov 2005 13:41:08 +0000 (+0000)
Subject: wip; before redo i2cs_interrupt
X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ijackson/git?a=commitdiff_plain;h=d532a2f9b6b4cee3788f66fd7d6c55db0c7ee80a;p=trains.git

wip; before redo i2cs_interrupt
---

diff --git a/detpic/i2clib.asm b/detpic/i2clib.asm
index 523e43b..f008d4d 100644
--- a/detpic/i2clib.asm
+++ b/detpic/i2clib.asm
@@ -11,8 +11,12 @@
 ; COMMON ADMINISTRATIVE ROUTINES
 
 		udata_acs
+
 t		res	1
 
+st		res	1
+st_subsequent	equ	0
+
 		code
 
 ;--------------------
@@ -20,9 +24,10 @@ i2cs_init
 ;	W		slave number		undefined
 		rcall	slave2addr2
 		mov_wf	SSPADD
-		mov_lw	0x16 ; !SSPEN, CKP(release), I2C 7-bit slave
+		clr_f	st
+		mov_lw	0x1e ; !SSPEN, CKP(release), I2C 7-bit slave S&P
 		mov_wf	SSPCON1
-		mov_lw	0x81 ; GCEN, SEN
+		mov_lw	0x01 ; !GCEN, SEN
 		mov_wf	SSPCON2
 		mov_lw	0x8 ; SMP(noslew), !CKE, !BF(empty)
 		mov_wf	SSPSTAT
@@ -37,24 +42,62 @@ i2cs_init
 i2cs_interrupt
 		bt_f_if0 PIR1, SSPIF
 		return
-; We have an interrupt.  What are the possibilities ?
+
+; We have an interrupt.  Firstly, clear the interrupt flag
+; so that if something else happens while we faff, the interrupt
+; will be regenerated:
+		bc_f	PIR1, SSPIF
+
+; Check that nothing is wrong:
+		mov_fw	SSPCON1
+		mov_wf	t
+		and_lw	0xc0
+		bra_nz	i2cs_interrupt_wcolsspov_endif
+		panic	morse_SV
+i2cs_interrupt_wcolsspov_endif
+
+; Find out what's just happened:
 		mov_ff	SSPSTAT, t
 
 chkval macro mask, value, label
 		mov_fw	t
+ if mask ^ 0xff
 		and_lw	mask
+ endif
 		xor_lw	value
 		bra_z	label
 		endm
 			; bits we want to check
-			;  80  60  20    04    02  01
-			;  SMP CKE D_A   R_W   UA  BF
-			;  set clr data? read? clr full?
+			;  80  60  20    10    08    04    02  01
+			;  SMP CKE D_A   P     S     R_W   UA  BF
+			;  set clr data? stop  start read? clr full?
+
+		chkval	0xff, 0x90, s_case_writing_stop
+		chkval	0xff, 0x89, s_case_addr_recv_write
+		chkval	0xff, 0x8d, s_case_addr_recv_read
+		chkval	0xff, 0xa9, s_case_write_data_recv
+		chkval	0xff, 0xac, s_case_read_data_sent
+		chkval	0xff, 0xa8, s_case_read_data_nack
+		chkval	0xdb, 0x90, s_case_unknown_stop
+		chkval	0xdb, 0x88, s_case_unknown_start
+
+		mov_ff	t, WREG2 ; fixme
+		panic	morse_SI
+
+;----------
+s_case_unknown_stop
+s_case_unknown_start
+		return
+
+;----------
+s_case_got_write_addr
+		
 
-		chkval	0xe3, 0x81, got_addr
-		chkval	0xe7, 0xa1, got_data_write
-		chkval	0xe7, 0xa4, sent_data_read
+		mov_fw	SSPBUF
+		and_lw	0xfe
+		bra_nz	nonzero
 
+		mov_wf	t
 		
 
 		mov_fw	SSPSTAT