/* PRG format
 *   Contains two bytes of header data, address from which
 *   the rest of the file will be loaded into memory.
 * BASIC memory starts at addr 2048, we effectively place "10 SYS 2064"
 * and an end of program after it. Then immedately afterwards
 * we place our command on addr 2064.
 *   When BASIC loads up, it runs "10 SYS 2064" and passes up execution there.
 *   Then, when we return, we get a zero which indicates termination.
 */

/* The starting address is defined by the value (label or alias) "main".
 * Since in basic we need to provide a decimal string, but we store a decimal value, we need
 * to do this complicated convertion.
 */
#define addr_to_ch(addr)                            \
	"0" + addr / 10000,                         \
	"0" + (addr - addr / 10000 * 10000) / 1000, \
	"0" + (addr - addr / 1000 * 1000) / 100,    \
	"0" + (addr - addr / 100 * 100) / 10,       \
	"0" + addr - addr / 10 * 10

.word $0801 ; Header -- addr 2049
* = $0801   ; Program Counter

.(
	.word eol
	.word 10
	.byt $9e," ",addr_to_ch(main),0
eol	.word 0
.)

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