************************************

* Display the 6809 registers to standard error

* OTHER MODULES NEEDED: BIN2HEX, BIN_HEX,  PUTS


* ENTRY: none
* EXIT: none


* NOTE: The value used for PC is that of the calling routine
*       S is assumed to be 2 greater than actual to comp for
*       the subroutine call...


 nam Show Register Values
 ttl Assembler Library Module


 section .data

count rmb 1 counter for 9 regs.
buffer rmb 8 buffer for ascii strings
cc.r rmb 1 offsets to access values
a.r  rmb 1
b.r  rmb 1
dp.r rmb 1
x.r  rmb 2
y.r  rmb 2
u.r  rmb 2
s.r  rmb 2
pc.r rmb 2

 endsect

 section .text

SHO_REGS:
 leas -2,s room for copy of <S>
 pshs cc,a,b,dp,x,y,u save rest
 leas -cc.r,s room for ascii strings
 tfr s,x
 leax pc.r,x get old <S>
 stx s.r,s stick on stack
 leay cc.r,s point to regs
 leau text,pcr register names
 clr count,s int. counter

* now we loop and display all the registers

loop1
 leax buffer,s point to ascii buffer
 ldd ,u++ get reg. name
 std ,x++
 lda #'= add a "="
 sta ,x+
 lda count,s 1st 4 are 1 byte
 cmpa #4
 bhs loop2 no, do a 2byte
 ldb ,y+ get single value
 lbsr BIN2HEX
 std ,x save ascii number
 clr 2,x
 bra report go report
loop2
 cmpa #9 done all?
 bhs exit yes, go home
 ldd ,y++ get reg value
 lbsr BIN_HEX convert it

* report reg. value

report
 leax buffer,s start of buffer
 lda #2 std err
 lbsr FPUTS print it
 ldb #$20 space
 lbsr FPUTC
 inc count,s do next reg
 bra loop1

exit
 ldb #$0d
 lda #2
 lbsr FPUTC start new line
 leas cc.r,s clear up stack
 puls cc,a,b,dp,x,y,u
 leas 2,s
 rts go home

text
 fcc /cc/
 fcc / a/
 fcc / b/
 fcc /dp/
 fcc / x/
 fcc / y/
 fcc / u/
 fcc / s/
 fcc /pc/

 endsect